Message Quarantine Campaign with Overlying Potential

By Dylan Main, Cofense Phishing Defense Center 

Message quarantine phish are back, this time with a new tactic utilizing the targeted company’s homepage as part of the attack. The Cofense Phishing Defense Center (PDC) has identified this campaign which attempts to steal employee credentials by posing as a message quarantine email. Using an overlay tactic to disguise itself, this attack is an example of how threat actors are using more advanced techniques to make these malicious emails appear as though they are from a trusted source. 

Figure 1: Phishing Email

This campaign attempts to imitate the technical support team of the employee’s company and makes it appear as though the company’s email security service has quarantined three messages, blocking them from entering the inbox. It claims these messages failed to process and need to be reviewed in order to confirm validity. It even states that two of these were considered valid and are being held for deletion. This could potentially lead the employee to believe that the messages could be important to the company and entice the employee to review the held emails. Another social engineering technique the threat actor uses to lure the employee into interacting with the email is giving the messages urgency, asking the recipient to review them or they will be deleted after three days. Potential loss of important documents or emails could make the employee more inclined to interact with this email.

Figure 2: Phishing Email 

As seen in Figure 2, hovering over “Review Messages Now” shows the malicious URL. However, upon interacting with the link, the user will be directed to a phishing page unique to the employees’ company. Here is where this campaign uses advanced mechanics to make it appear even more legitimate. 

Figure 3: Cofense Phishing Page 

After interacting with the email, the employee will then be redirected to what appears to be a login screen on the company website (Fig 3). However, further analysis has determined that the page shown is actually the company’s website home page with a fake login panel covering it. This gives the employee a greater comfort level, by displaying to  a familiar page. It is also possible to interact with this page by moving outside of the overlay, showing that it is the actual page they have seen and used before. The overlay itself is attempting to prompt the user to sign in to access the company account. The entered credentials are then sent to the threat actor, giving them access to the target’s company account. 

Figure 4: Microsoft Phishing Page

Based on the analysis performed by the PDC, it was determined that each link, while still going to the same base domain, uses specific parameters to determine which web page pull, then overlays the fake login panel on top. Depending on what company the threat actor is targeting, the link will populate the address of the original recipient of the email. Figures 3 and 4 are examples provided by entering an address, in this case Cofense or Microsoft.  After the equal sign, the link will look at the domain of that address and pull the homepage. This campaign shows that threat actors can and will use any resource available to compromise business accounts.  

HOW COFENSE CAN HELP 

Cofense Resources 

Cofense PhishMeTM offers a simulation template named Email Quarantine Report – Alternate. 

Network IOC IP   
hxxp://google[.]com@ashousingcompany[.]com/www/?email=  104[.]27[.]158[.]208 
hxxp://traximgarage[.]com/www/webmail-std/appsuite/1ogin/mai1/  185[.]68[.]16[.]137 
All third-party trademarks referenced by Cofense whether in logo form, name form or product form, or otherwise, remain the property of their respective holders, and use of these trademarks in no way indicates any relationship between Cofense and the holders of the trademarks. Any observations contained in this blog regarding circumvention of end point protections are based on observations at a point in time based on a specific set of system configurations. Subsequent updates or different configurations may be effective at stopping these or similar threats.
The Cofense® and PhishMe® names and logos, as well as any other Cofense product or service names or logos displayed on this blog are registered trademarks or trademarks of Cofense Inc.

Phishing Threat Preys on Desperate Business Owners

By Kyle Duncan and Noah Mizell, Cofense Phishing Defense Center

For the past few months, businesses across the nation have suffered from the financial strain brought on by COVID-19. Government relief has become a major concern as businesses struggle to stay afloat. The Cofense Phishing Defense Center (PDC) has taken notice of a new phishing campaign that once again aims to abuse Covid-related fear and uncertainty. This campaign imitates the U.S. Small Business Administration (SBA) to harvest the credentials of business owners who may be expecting the administration’s assistance.

While the spoofed address for this attack is one the SBA uses and is even listed on their website, one brief look at this example’s “Received” path shows it did not originate from the SBA.

Figure 1-2: Email Header

These first four stops on the email’s Received path indicate that the email originated from Japanese email servers. This can not only be seen in the Received path but also in other fields of the header information. The Japanese IP address is seen in the Authentication-Results-Original and the Japanese domain can be seen in the Message-ID in some cases.

Figure 3-4: Email Body

The email body of this phish is very clean and well-constructed. Barring the excessive use of commas, the email looks legitimate at a glance. The threat actor has even compiled legitimate logo images and contact information to help sell the deception. Small business owners who have applied for federal aid would be hopeful and relieved to see this message in their inbox.

When you hover over the “Review and Proceed” button, however, the facade falls. Instead of sending users to SBA.gov, this button will redirect to the phishing page:

hXXps://ion-homes[.]com/sba/covid19relief/sba.gov/

The phishing page at this URL redirects to an SBA phishing login page with similar logo, positioning, and details to the real site. While the phishing domain differs, the threat actor has notably attempted to mirror the URL structure from the legitimate SBA’s login URL by tossing in ‘covid19relief’ into the directory name.

Figure 5: Phishing Page

Upon entering their login credentials, users are then redirected to the official SBA website, specifically the login page as seen in Figure 5.

Figure 6: Official Small Business Association Page

Instead of receiving aid, business owners who fall for the scam give away their credentials—adding insult to injury.

LEARN MORE about the Cofense Phishing Defense Center. See how the PDC’s managed phishing response and remediation stops phishing attacks that elude email gateways.

Network IOC  IP  
hXXps://ion-homes[.]com/sba/covid19relief/sba.gov/ 173.231.209.178
All third-party trademarks referenced by Cofense whether in logo form, name form or product form, or otherwise, remain the property of their respective holders, and use of these trademarks in no way indicates any relationship between Cofense and the holders of the trademarks. Any observations contained in this blog regarding circumvention of end point protections are based on observations at a point in time based on a specific set of system configurations. Subsequent updates or different configurations may be effective at stopping these or similar threats.
The Cofense® and PhishMe® names and logos, as well as any other Cofense product or service names or logos displayed on this blog are registered trademarks or trademarks of Cofense Inc.

Threat Actors Bypass Gateways with Google Ad Redirects

By Dylan Main and Harsh Patel, Cofense Phishing Defense Center

The Cofense Phishing Defense Center (PDC) has observed a phishing campaign that attempts to steal Office 365 login credentials by luring employees to accept a new Terms of Use and Privacy Policy. This new campaign has been seen across multiple organizations and uses advanced techniques to garner employee login credentials, including a Google Ad Services redirect to fool email gateways.

Figure 1: Headers

The originating IP in the headers of this email proved its source was coming from a legitimate account with the ‘from’ address “info@jtpsecurity[.]co[.]za” It appeared as though this email address was compromised and then used to send the phish to multiple employees. The word “security” in the from address could potentially lull the user into trusting the email’s origin.

Figure 2: Email Preview

At first glance, the user will see “This message was sent with High Importance.” Again, the from address contains the word security and the subject talks about a “Recent Policy Change,” creating urgency to click and handle the matter immediately.

The email body talks about accepting the newly updated “Terms of Use & Privacy Policy.” Also, it notes how this new policy will affect personal data and discontinue all active services on the user’s account. Curious users will likely want to “Learn More.”

Figure 3 shows the URL embedded in both buttons, “Accept” and “Learn More”:

Figure 3: URL redirect of the buttons

As seen in the above figure, the threat actor has utilized a Google Ad Services redirect to pilot users to their phish. This suggests that the threat actor(s) may have paid to have the URL go through an authorized source. In turn, this easily bypasses secure email gateways and exposes employees to the phish.

Upon clicking on either button, users are redirected to a duplicate of the real Microsoft page at the URL:

hXXps://microsoftoffice-servicepolicy-onlineserver[.]comisys[.]host/common/oauth2-authorize

 On this page users are presented with a pop up of the privacy policy the email mentions. In this window there are two notable logos as well, a Microsoft logo and the user’s company’s logo, in a bid to make this page appear that much more legitimate. Scrolling through the text box you can see the Privacy Statement was taken from Microsoft’s website.

Figure 4: First Page of the phishing attack

After accepting the updated policy, the user is then redirected to a Microsoft login page, which impersonates the Office 365 login page. An employee who enters their credentials and clicks “Next” will have sent the Threat Actor(s) their Microsoft credentials and compromised their account.

Figure 5: Second Page (The actual phishing)

Following the login page, users find further reason to believe the update is legitimate, one more box saying, “We’ve updated our terms.” Upon clicking the “Finish” button, they’ll be all set.

Figure 6: Third Page (Post entering credentials)

Last step: users are redirected to the legitimate Microsoft page, their Service Agreement, to complete the scam. Nothing malicious here!

Figure 7: Final Page (Official Microsoft site)

LEARN MORE about the Cofense Phishing Defense Center. See how the PDC’s managed phishing response and remediation stops the phishing attacks that elude email gateways.

Indicators of Compromise:

Network IOCs IP  
hxxps://www[.]googleadservices[.]com/pagead/aclk?sa=L&ai=C3seiJpC5XstooZGJBrPArsADp__a3lyH_4PTjAqoqKfonA8QASC7-_keYISV7IXcHaABzavQ-gPIAQmpAt6UwcHeNU0-qAMByANKqgTEAU_Q2dNvWCQ_LtumFUNLEz16PFVhg8cC3HmYEdlxma4KWUfGkvbdLFpKvCC92odSoiBTw9idw1iHRgreOTD1xyzoBBif4axm3JFTnekl_2_OeuLDQv0U_HzVVt10Iu5SkzsX6nGWyfUgPHIgJkxJqY4me8SG8d0nlmJ8PumQhJhze02bPmqEr4puzh2awPAoHoVPQ7QaXlbeJvf4W7Wexg1RGQ0EqMY8Z7YLfyh6tceagXiYGwWU1r3H9HuiISfj4G-RYYTABM-Sru2hAsAFBfoFBgglEAEYAJAGAaAGLoAHm9SvBYgHAZAHAqgHjs4bqAeT2BuoB7oGqAfw2RuoB_LZG6gHpr4bqAfs1RuoB_PRG6gH7NUbqAeW2BuoB8LaG9gHAMAIAdIIBggAEAIYGoAKAZALA5gLAcgLAYAMAeAS_6jY_crtxomjAdgTDg&ae=1&num=1&cid=CAMSeQClSFh3L5xTIDfFt35D8xjVEHFCYXr5NOlTRany4t_BBsFsAp3b7XCD0nSBKDirzhPVamy0H75uzx6gQxh5_rKDAlBAJWTUCf1Tqi6saFbojDtHd_R8dtCePj4ZvH0zHZWyRITLXvztggY2ibrWY9oLm5X8Wcuetvk&sig=AOD64_0L9hd4oCjDoroDTf6-7Fkon2bwsw&ctype=5&client=ca-pub-1169945711933407&adurl=https%3A%2F%2Fmicrosoftoffice-servicepolicy-onlineserver[.]comisys[.]host172[.]217[.]7[.]226
hxxps://microsoftoffice-servicepolicy-onlineserver[.]comisys[.]host/198[.]23[.]137[.]146
All third-party trademarks referenced by Cofense whether in logo form, name form or product form, or otherwise, remain the property of their respective holders, and use of these trademarks in no way indicates any relationship between Cofense and the holders of the trademarks. Any observations contained in this blog regarding circumvention of end point protections are based on observations at a point in time based on a specific set of system configurations. Subsequent updates or different configurations may be effective at stopping these or similar threats.
The Cofense® and PhishMe® names and logos, as well as any other Cofense product or service names or logos displayed on this blog are registered trademarks or trademarks of Cofense Inc.

Invoice Themed Phishing Emails Are Spreading from Trusted Links

By: Kian Mahdavi, Cofense Phishing Defense Center

The Cofense Phishing Defense Center (PDC) is seeing continued growth in phishing attacks which harvests users’ credentials via genuine file-sharing websites, which are found in environments protected by Proofpoint’s Secure Email Gateway (SEG). A huge factor in this campaign is the confidence users have in emails containing the “trusted” Dropbox reference.

It is tricky for SEGs to keep up with attempts to spread phishing attacks and malware via sharing services such as Dropbox, ShareFile, WeTransfer, Google Docs, Egnyte and even SharePoint. Fortunately, a few of our clients’ users reported the phishing emails via the Cofense Reporter button.

The “traditional” methodology for attackers was to “break in.” Nowadays, they easily can “login,” thanks to sharing sites.

Figure 1 – Body of email showcasing the victory of this attack tying in with user interaction

The spear phishing attack sends a link requesting users to access a purchase order form with a (.pdf) extension. Upon clicking, the attack automatically redirects the user to their default web browser, requesting to click the “Download” button. The website will begin the download inside the “Downloads” folder. Nothing sinister going on, right?

The ‘sent addresses’ TLD – “actionsportsequipment[.]com” – coincidentally relates to the nature of the client’s industry; this demonstrates the extent the attackers went to, in a bid to slip through the “secure” environment. One must question themself: “Was I expecting this transfer?” and “Am I expecting to receive a purchase order from this sender?”

Moreover, since the emails have been authenticated against Dropbox’s internal servers, the emails pass basic email security checks such as DKIM and SPF.

Figure 2 & 3 – Downloadable purchase order file

Once the download has been completed, the user is prompted to open the (.html) link assuming the “purchase order” form would appear, however upon clicking, the campaign redirects the user to a supposed “Microsoft” login page.

In this case, the attackers used the free website builder “Weebly.com” … yet another legitimate source, further deceiving the security measures in place with trusted redirect domains and IPs which will naturally continue to be white-listed and deemed “safe” since millions of users share data with one another on a daily basis.

For this reason, the presence of the padlock appears, adding not only security on both parties, but also the illusion that the website is “secure.”

Figure 5 – Phishing site built by Weebly

Once credentials have been supplied, the campaign redirects the user to the authentic ‘office[.]com’ webpage, which could even be enough to assure users it was a genuine procedure. A user’s personal data could potentially be in the hands of the threat actor, assuming they logged in with their true Microsoft credentials.

Figure 6 – Redirect to Microsoft Office webpage  

Indicators of Compromise:

Network IOC IP
hXXps://www[.]dropbox[.]com/l/AADOPQGXtuDK03QYuvJqI0MbDlDxBTV28Cs
hXXps://www[.]dropbox[.]com/l/AAAtWq-LVZcqXBnFLinUi9rB3LpEijuPo78
162[.]125[.]6[.]1
hXXps://helpsupport0ffice20[.]weebly[.]com/ 199[.]34[.]228[.]53
199[.]34[.]228[.]54

LEARN MORE about the Cofense Phishing Defense Center. See how the PDC’s managed phishing response and remediation stops the phishing attacks that elude email gateways.

All third-party trademarks referenced by Cofense whether in logo form, name form or product form, or otherwise, remain the property of their respective holders, and use of these trademarks in no way indicates any relationship between Cofense and the holders of the trademarks. Any observations contained in this blog regarding circumvention of end point protections are based on observations at a point in time based on a specific set of system configurations. Subsequent updates or different configurations may be effective at stopping these or similar threats.
The Cofense® and PhishMe® names and logos, as well as any other Cofense product or service names or logos displayed on this blog are registered trademarks or trademarks of Cofense Inc.

HMRC latest target in global COVID relief phishing campaigns

By Jake Longden, Cofense Phishing Defense Center

Taxes and rebates have long been some of a phisher’s favorite targets. Now the coronavirus has provided a fresh new way to exploit this topic: the government grants designed to help small businesses and those out of work due to the pandemic.

The Cofense Phishing Defense Center (PDC) has observed a new phishing campaign in the U.K. that aims to harvest HMRC (Her Majesties Revenue and Customs) credentials and sensitive personal information by preying on employees who are expecting COVID relief grants.

With multiple world governments providing such grants, this is an easily modifiable tactic—simply modify the email to spoof the target country’s tax service.

Figure 1: Email Header

To add authenticity to the email, the threat actors have used an email address (hmrc@hotmail.com) with the impersonated organization in the name and set the name to match (HM Revenue & Customs). That, combined with the subject line, is a great way to attract the user’s interest (“Helping you during this covid from government”). Whilst this sentence is not using the greatest grammar, who wouldn’t want government assistance during these difficult times?

Figure 2: Email Body

When first viewing the email, the user is presented with a notification that the government is offering between £2500 and £7500 in tax grants for those whose work has been affected by the virus. The email includes a link to check their eligibility. With the government publicly and repeatedly mentioning such sums,  the email is believable to inattentive users. The attacker also mentions the “Open Government License v3.0,” a legitimate copyright license used by the Government and Crown Services, to provide additional credibility.

Figure 3: Phishing Page

Once the link is clicked, the user is presented with a realistic clone of the GOV.UK website. This may alleviate concerns a user may have and provide a false sense of security, as the page is extremely similar to the HMRC account sign-in page. The biggest red flag: the URL, just-bee.nl, is not relevant.

Figure 4: Phishing Page

Figure 5: Phishing Page

Here the user is asked to enter some very personal and sensitive data. Another sign that this is a scam: the volume and sensitivity of data requested far exceeds what is required to sign into a legitimate account. The data requested here screams “identity theft/impersonation.”

From there, the user is directed to a page that seems to be loading, to help provide the impression that the data is being processed and an eligibility check performed.

Figure 6: Processing Page

 

Network IOC IP
hXXps://www[.]lagesports[.]com/[.]tmb/xml[.]php 69[.]10[.]32[.]186
hXXps://rtoutletpremium[.]com[.]br/[.]well-known/pki-validation/UTR/index[.]php 162[.]241[.]182[.]5

 

How Cofense Can Help

Visit Cofense’s Coronavirus Phishing Infocenter to stay up to date as threats evolve. Our site is updated with screenshots and YARA rules as we continue to track campaigns.

All third-party trademarks referenced by Cofense whether in logo form, name form or product form, or otherwise, remain the property of their respective holders, and use of these trademarks in no way indicates any relationship between Cofense and the holders of the trademarks. Any observations contained in this blog regarding circumvention of end point protections are based on observations at a point in time based on a specific set of system configurations. Subsequent updates or different configurations may be effective at stopping these or similar threats.
The Cofense® and PhishMe® names and logos, as well as any other Cofense product or service names or logos displayed on this blog are registered trademarks or trademarks of Cofense Inc.

New Covid-19 Phish Abuses Tax Relief Act to Steal Credentials

By Ashley Atkins, Cofense Phishing Defense Center

For the past few months, the Cofense Phishing Defense Center (PDC) has observed numerous phishing campaigns associated with the coronavirus (COVID-19) pandemic.  These COVID-19-themed phish come in various forms and tend to prey on those fearful of contracting the disease as well as those who are in dire need of economic relief. Recently, the PDC identified a unique version that deserves an overview.

For this attack the user received a malicious email impersonating the US Department of Revenue with the subject: CARES Relief Certificate. The message body references information regarding the 2019 185 Act that has received attention in media outlets and social platforms. Upon researching the Act, it is highly likely the attacker copied that information from a website, made minor changes and created this phishing email, as seen in Figure 1 below.

Figure 1: Email Body

At a glance, this email simply informs users of the tax provisions adopted from the CARES Relief Act and outlines the details regarding it. It also mentions a deadline for applying, and that in order to apply users must fill out an attached secure document. One thing to note, this email arrived a few days after the stated deadline in the email. This may be intentional on the threat actor’s part in order to instill a sense of urgency in users – “you’re late and the deadline has passed!” However, some users may be pressed enough to attempt to apply, thinking it is worth a shot if it could mean receiving relief during this pandemic.

Many obvious red flags are present in this email. Besides the unsightly format, grammatical errors and random property address, the most evident red flag is the sender’s address. The attacker has abused AWeber’s email marketing service. AWeber’s use of SenderID authentication results in the “From” line showing as “Department of Revenue <state=lrs-gov[.]tk[@]send[.]aweber[.]com> on behalf of Department Of Revenue <state[@]lrs-gov[.]tk>”. When reviewing the domain, it seems to read as “Irs” (IRS), but the first letter is actually a lower-case L. The use of the .tk top-level domain (TLD) is worth noting as well. This TLD is the country code for a New Zealand territory called Tokelau. It is also free and one of the top TLDs used in phishing attacks.

Should users go so far as to download and open the “secure” HTML attachment, they are presented with a typically formatted Microsoft login page. This may appear odd, as the threat actor has impersonated a well-known and trusted entity such as the US Department of Revenue.

The fake Microsoft login page prompts for the standard username and password.

Figure 2: Phishing Page

Once credentials are submitted, a PHP script sends the stolen information to the attacker. The HTML’s source code attempts to bypass URL detection by using base tags that splits the malicious URLs into two sections.

Figures 3- 5: Source Code

Network IOCs IP
hxxps://youdiaddy[.]ml/api/api[.]php? 192[.]236[.]194[.]247
hxxps://ijodaddy[.]cf/api/api[.]php? 23[.]254[.]230[.]115

 

All third-party trademarks referenced by Cofense whether in logo form, name form or product form, or otherwise, remain the property of their respective holders, and use of these trademarks in no way indicates any relationship between Cofense and the holders of the trademarks. Any observations contained in this blog regarding circumvention of end point protections are based on observations at a point in time based on a specific set of system configurations. Subsequent updates or different configurations may be effective at stopping these or similar threats.The Cofense® and PhishMe® names and logos, as well as any other Cofense product or service names or logos displayed on this blog are registered trademarks or trademarks of Cofense Inc.

MFA Bypass Phish Caught: OAuth2 Grants Access to User Data Without a Password

By Elmer Hernandez, Cofense Phishing Defense Center (PDC)

The Cofense Phishing Defense Center (PDC) uncovered a phishing tactic that leverages the OAuth2 framework and OpenID Connect (OIDC) protocol to access user data. The phish is not a typical credential harvester, and even if it was, Multi-Factor Authentication (MFA) wouldn’t have helped. Instead, it attempts to trick users into granting permissions to a rogue application. This is not the first time the tactic has been observed, but it’s a stark reminder that phishing isn’t going to be solved by Multi-Factor Authentication.

Using the lure of a Q1 bonus, the email is crafted to appear to be a normal invite to a SharePoint hosted file. The prospect of receiving an increase to their salary is an effective lure that can lead users to fall prey.

Figure 1 – Email Body

After clicking on the link, users are taken to the legitimate Microsoft Office 365 login page at https://login.microsoftonline.com (Figure 2). However, if one inspects the URL in its entirety, which average users are unlikely to do, a more sinister purpose is revealed.

Figure 2 – O365 Login Page

Anatomy of a URL

First, a quick primer: applications that want to access Office 365 data on behalf of a user do so through Microsoft Graph authorizations. However, they must first obtain an access token from the Microsoft Identity Platform. This is where OAuth2 and OIDC come in. The latter is used to authenticate the user who will be granting the access, and if authentication is successful, the former authorizes (delegates) access for the application. All of this is done without exposing any credentials to the application.

Figure 3 – Entire URL

The response_type parameter denotes the type of access being requested to the Microsoft Identity Platform /authorize endpoint. In this case, both an ID token and an authorization code (id_token+code) are requested. The latter will be exchanged for an access token which will, in turn, be presented by the application to Microsoft Graph for data access.

Next, the redirect uri parameter indicates the location to which authorization responses are sent. This includes tokens and authorization codes. As we can see, responses are sent to hxxps://officehnoc[.]com/office, a domain masquerading as a legitimate Office 365 entity, located at 88[.]80[.]148[.]31 in Sofia, Bulgaria and hosted by BelCloud.

Moving on, the scope parameter shows a list of permissions the user gives to the application (note “%20” represents a blank space). These allow the application to read (read) and/or modify (write) specific resources for the signed in user. If the “All” constraint is present, permissions apply for all such resources in a directory.

For example “contacts.read” enables the application to read only the user’s contacts, whereas “notes.read.all” allows it to read all OneNote notebooks the user has access to, and “Files.ReadWrite.All” to both read and modify (create, update and delete) all files accessible to the user, not only his or her own.

If the attackers were successful, they could grab all the victims’ email and access cloud hosted documents containing sensitive or confidential information. Once the attacker has sensitive information, they can use it to extort victims for a Bitcoin ransom. The same permissions can also be used to download the user’s contact list to be used against fresh victims. Using the address book and old emails would allow the attacker to create hyper-realistic Reply-Chain phishing emails.

Perhaps most concerning however is “offline_access” As access tokens have an expiration time, this permission allows the application to obtain refresh tokens, which can be exchanged for new access tokens. Therefore, users need only to authenticate and approve permissions once to potentially enable indefinite access to their data.

Finally, we find openid and profile which are technically scopes in themselves; openid indicates the application uses OIDC for user authentication, while profile provides basic information such as the user’s name, profile picture, gender and locale among others. This information, known as claims, is sent to the application in the ID token issued by the /authorize endpoint.

After signing in, the user will be asked to confirm one last time that he or she wants to grant the application the aforementioned permissions. If users fail to act, it will be up to domain administrators to spot and deal with any suspicious applications their users might have misguidedly approved.

The OAuth2 phish is a relevant example of adversary adaptation. Not only is there no need to compromise credentials, but touted security measures such as MFA are also bypassed; it is users themselves who unwittingly approve malicious access to their data.

Network IOC IP
hxxps://officehnoc[.]com:8081/office 88[.]80[.]148[.]31

 

How Cofense Can Help

Visit Cofense’s Remote Work Phishing Infocenter to stay up to date as threats evolve. Our site is updated with screenshots of real phish that have evaded secure email gateway detection and other helpful resources so you can help keep your organization protected.

All third-party trademarks referenced by Cofense whether in logo form, name form or product form, or otherwise, remain the property of their respective holders, and use of these trademarks in no way indicates any relationship between Cofense and the holders of the trademarks. Any observations contained in this blog regarding circumvention of end point protections are based on observations at a point in time based on a specific set of system configurations. Subsequent updates or different configurations may be effective at stopping these or similar threats.
The Cofense® and PhishMe® names and logos, as well as any other Cofense product or service names or logos displayed on this blog are registered trademarks or trademarks of Cofense Inc.

New Phishing Scam Targets Teleworkers with Bogus Microsoft Teams Notification

By: Kian Mahdavi, Cofense Phishing Defense Center

With the influx of remote workers, it’s a perfect opportunity to flood people’s inboxes with malicious emails and fake links. The Cofense Phishing Defense Center (PDC) recently uncovered a phishing campaign that targets employees to harvest their Microsoft credentials. Ironically, the phish was found in an environment protected by Microsoft’s own secure email gateway (SEG). The phishing email, which was reported to the PDC using the Cofense Reporter button, included a well thought out “AudioChat” notification link supposedly from Microsoft Teams.

Teams is one of the most popular platforms for remote employees. Predictably, the threat actors have taken this into consideration – especially during the COVID-19 pandemic with millions of people teleworking. We expect this trend to continue with similar communication platforms.

Figure 1: Email Body of an official Microsoft Teams example notification

Figure 2: Email Body of illegitimate Microsoft Teams notification

Credit where credit’s due, we were impressed by the effort of the threat actor and their high-quality social engineering tactics. The subject line reads “Chat Message in Teams”- is this just an ordinary notification?

The email content has perfect similarities between Microsoft’s services; in particular, it incorporates matching font size and color as well as the overall layout. The email also includes the generic ‘tips’ section towards the bottom half of the message, evident above in Figure 2. However, there’s a catch: despite the solid efforts of the email content, there are a few tell-tale indications this is a phish. The most obvious sign is the sender’s lengthy spoofed email address:

matcnotification[.]teamadmin_audidsenderderweeu44we7yhw[@]ssiconstructionnw[.]com

The words “notification” and “teamadmin” have been skilfully included within the account name. But more importantly, the TLD – “ssiconstructionwn” – does not contain the all-important ‘Microsoft’ reference. No prize for guessing, it is a construction company located in Seattle, Washington that the attacker has spoofed. Since the TLD is from a legitimate source, not only does it pass basic email security checks, such as DKIM and SPF, but also provides HTTPS displaying the essential green lock to the left of the URL, located below in Figure 3 – a valiant effort on behalf of the threat actor.

On top of that, the text displays: “Teammate sent you an offline message.” Notice the message practices a generic word: “teammate” rather than the specific name of the sender. Contradicting itself, the email includes an initial (JC) of the supposed sender within the avatar, further hindering the legitimacy of the email and raising suspicion.

As mentioned above, the user is requested to click on the “16 second AudioChat,” and once hovered, displays the following link:

hXXps://us19[.]campaign-archive[.]com/?u=0dce22c9638fc90b5c17ea20a&id=6652f42d20

The user’s email address (now redacted) is embedded into the above URL. Companies often use various email protection solutions, and as a result, URLs are often packaged with security phrases. In this phishing campaign, the email contains the words “safelinks.protection” planted at the very beginning of the hover link. This could trip up inquisitive readers who might overlook the rest of the URL and click.

Figure 3: Initial Phishing Page

The phishing page above, where users are forwarded, adheres to Microsoft’s protocol (an almost picture-perfect replica); of course, we are overlooking the forged URL within the web-bar. Once ‘Open Microsoft Teams’ has been clicked, the user should have been automatically redirected to the Microsoft Teams application. Instead, the user is taken on a slight detour to the final link of this phishing attack:

hXXps://imunodar[.]com/wp-content/plugins/wp-picaso/Teams/

Figure 4: Secondary Phishing Page

Once credentials have been supplied, the campaign redirects the user to the authentic ‘office[.]com’ webpage, which could even be enough to assure users it was a genuine procedure. A user’s personal data could potentially be in the hands of the threat actor, assuming they logged in with their true Microsoft credentials.

Indicators of Compromise:

Network IOC IP
hXXps://us19[.]campaign-archive[.]com/?u=0dce22c9638fc90b5c17ea20a&id=6652f42d20
hXXps://imunodar[.]com/wp-content/plugins/wp-picaso/Teams/
104[.]118[.]190[.]227

 

How Cofense Can Help

Visit Cofense’s Remote Work Phishing Infocenter to stay up to date as threats evolve. Our site is updated with screenshots of real phish that have evaded secure email gateway detection and other helpful resources so you can help keep your organization protected.

 
All third-party trademarks referenced by Cofense whether in logo form, name form or product form, or otherwise, remain the property of their respective holders, and use of these trademarks in no way indicates any relationship between Cofense and the holders of the trademarks. Any observations contained in this blog regarding circumvention of end point protections are based on observations at a point in time based on a specific set of system configurations. Subsequent updates or different configurations may be effective at stopping these or similar threats.
The Cofense® and PhishMe® names and logos, as well as any other Cofense product or service names or logos displayed on this blog are registered trademarks or trademarks of Cofense Inc.

A Not So Relieving Tax Relief Email: Threat Actors Take Aim at US Stimulus Efforts

By Ashley Tran, Cofense Phishing Defense Center

The Cofense Phishing Defense Center (PDC) has observed a new phishing campaign that aims to harvest a variety of email credentials specifically from United States citizens.

Countries all around the world are providing relief programs to their citizens to help alleviate the financial strain as a result of the COVID-19 pandemic. This threat actor, however, targets US relief efforts and the citizens who need it most. This email campaign uses the logo of the Internal Revenue Service (IRS) to bolster its credibility.

Figure 1: Email Preview

The threat actor made both the subject and sender information eye catching, as seen in Figure 1. The email appears to be from ‘IRS GOV’ regarding the subject “Tax Relief Fund,” which would be enough to gain the attention of anyone, especially those who may not have received their relief or need more. Upon clicking into the email, users are presented with the following message, as seen in Figure 2 below.

Figure 2-3: Email Body

Despite the image missing from this email sample, assumed to once have been a DocuSign logo based on the image description, the email may appear legitimate at first glance. The IRS has sent a secure document via DocuSign along with a security code to view it, but it must be used soon as it will “expire.” The email is also marked “High Importance.”

A closer look at the body of the email reveals many warning signs this email is a phish. Anyone acquainted with DocuSign would know this is not what an invitation from the service looks like. Not to mention there is odd spacing and capitalization found in the text – atypical for professional emails. There is also mention of a security code that must be used “before expiration,” a common social engineering tactic used to illicit a sense urgency.

The link found in the email, “View Shared Folder,” redirects users to the phishing site located at:

hxxp://playdemy[.]org/office/doc-new

Figures 4-5: Phishing Page and Confirmation Page

Figures 4-5 are examples of the first page users will see upon navigating through the link found in the email. The page is a simple DocuSign page prompting for the user’s email address in order to access the promised document. Visually there aren’t many differences compared to DocuSign’s website, other than the incorrect URL displayed in the address bar. However, the threat actor may have intentionally used a .org-based domain to make it appear safe, as many end users have heard .org top-level domains are “secure.”

Should a user proceed to enter their email address on this page, they are prompted once again to verify the information before being redirected to the next step of this attack.

Figures 6-7: AOL login page

The next step involves redirecting users to a phishing page based on their email provider. In Figures 6-7 above, we used a dummy AOL email and were redirected to an AOL phish. The attacker’s AOL login page rivals the look and feel of AOL’s — the only real difference is the incorrect URL in the address bar. The email entered in the first step is already pre-filled as well. This same occurs with other email providers inputted into the first step of the attack. Figures 8-10, for example, show the Gmail phish that users are redirected to if that was the email provider they entered.

Figures 8-10: Alternative Gmail Phish

Should a user enter an email address to proceed this far, the threat actor has made sure to ask for further compromising information, as seen in Figure 10: a recovery number or recovery email address per their back-up login information.

Figure 11: Final Destination

Regardless of the email address, and should the user enter this information, users are then redirected to an unexpected document; in lieu of the promised “Tax Relief Fund,” they see a completely unrelated academic paper hosted on Harvard Business School’s website. This is a common tactic, designed to confuse users into thinking there is nothing amiss, that perhaps this was a mistaken exchange or they received the wrong document in error and must wait for further contact.

Further analysis of the website utilized for this attack yielded further information on the attack and the actors behind it.

Figure 12: Open Directory

Upon navigating to the main domain, as shown in Figure 12, an open directory appears. While the file Chetos.php is password protected at present, the file 039434.php exposes a greater security threat that can be observed in Figure 13, a web shell.

Figure 13: WebAccess Shell

The beginnings of a malicious web shell start with an attacker methodically installing the malicious script for the shell on the targeted site, either by SQL injection or cross-site scripting. From there the web shell is utilized by attackers to maintain persistent access to a compromised website without having to repeat all the work of exploiting the same vulnerability they used the first time – generally, a backdoor. They can remotely execute commands and manage files that they abuse to carry out their attacks, such as a phishing attack.
As observed in Figure 13, investigation of the shell reveals files from the open directory are displayed, last modified 2020-04-24 by “owner/group” “njlugdc”, otherwise known as the attacker. The real guts of this attack, however, can be found within the directory path office/doc-new seen in Figure 14.

Figure 14: office/doc-new Directory

Within the directory are the many steps in what appears to be a simple phish. There are multiple email branded folders such as “a0l”, “earthl1nk”, “gma1l,” all of which help the threat actor target email clients. Each of these email branded folders host a phish that is specifically tailored to that brand, allowing for a more “authentic” experience that lull users into a sense of security.

Figure 15: Code Behind the Attack

Figure 15 demonstrates the code behind the attack that sanitizes user input to determine which of these phish a user is redirected to, along with the associated email brand logo to display during the redirect process.

Figure 16: Threat Actor Emails Exposed

Within the files contained in this web shell, the threat actor’s emails are displayed. Figure 16 shows the code of the Email.php file and information exfiltrated from users during the phishing attack that are sent to:
techhome18[@]gmail[.]com
we.us1[@]protonmail[.]com

Although the identity of the attacker behind this IRS phish is unknown, it is evident they took care to carefully craft this attack and chose to exploit a current event that is closely followed by Americans in an attempt to successfully steal as many log-in credentials as possible.

Network IOC IP
hxxp://playdemy[.]org/office/doc-new 206[.]123[.]154[.]15

 

 

All third-party trademarks referenced by Cofense whether in logo form, name form or product form, or otherwise, remain the property of their respective holders, and use of these trademarks in no way indicates any relationship between Cofense and the holders of the trademarks. Any observations contained in this blog regarding circumvention of end point protections are based on observations at a point in time based on a specific set of system configurations. Subsequent updates or different configurations may be effective at stopping these or similar threats.
The Cofense® and PhishMe® names and logos, as well as any other Cofense product or service names or logos displayed on this blog are registered trademarks or trademarks of Cofense Inc.

Phishers Continue to Spoof WebEx

By Kaleb Kirk, Cofense Phishing Defense Center

Last month, the Cofense Phishing Defense Center (PDC) observed a new phishing trend wherein threat actors spoofed WebEx pages to harvest Office365 (O365) credentials. Since the posting of the original blog, the PDC has seen an increase in the number of similarly themed WebEx phishing attacks, yet another example of attackers leveraging the rapid shift to remote work in light of COVID-19 concerns. As many organizations and their workforce are increasingly dependent on remote working tools and solutions, reducing the attack surface (the number of different approaches a threat actor can use to enter or extract data) of such online platforms and services is becoming even more critical.

Attackers know this and are constantly looking at ways to circumvent detection by secure email gateways and position themselves between users and legitimate services. The WebEx phishing campaign is a prime example, slipping past email protection to dupe users into providing their credentials out of fear they will be unable to use the service and perform their job otherwise.  It’s therefore not a surprise the PDC has seen an increase in phishing attacks that spoof legitimate, business critical services.

While this blog focuses on a new phishing campaign imitating WebEx, this style of attack can and has taken multiple forms, mimicking many different legitimate web services. Luckily however, once an end user knows some of the telltale signs,  it’s often easy to identify what is truly legitimate and what is fake.

Figures 1-2: Email Body

Upon an initial glance, this email may appear innocuous enough. It has the look and format one would likely expect when receiving an email from Cisco. The style is professional, the layout of the email isn’t mangled or chaotic, and it appears legitimate – an intentional and easy tactic to pull off. All the threat actor required was a real WebEx email to copy from in order to duplicate the style and alter select elements for nefarious purposes. The sender address appears to come from WebEx. However, this is what is known as the “friendly” from address – while the recipient sees the displaying address, which appears to be authentic, the email headers reveal a very different story. The problem with a “friendly” sender address is that it is easily spoofed by attackers; it’s a well-known, simple trick designed to convince the recipient that an email is legitimate.

Looking beyond simple aesthetics, however, other indicators of phishing are evident. The subject line indicates there is an issue with SSL certificates that requires the user to sign in and resolve. This is referenced further in the body of the email, providing a sense of legitimacy and enticing them to open the email and read it.

The wording of the email also employs scare tactics that are prevalent in phishing attacks. The recipient is informed there is a problem that has caused their service to become deactivated and the user must log-in and authenticate by clicking the link. Verbiage like this is often used to coerce the end user into clicking on a link or attachment in haste before they have time to fully think it through – a key tactic used by threat actors in phishing campaigns.

Finally, the link itself reveals something else is fishy about this alert. Hovering over the button shows the embedded link is not, in fact, a WebEx page, but a SendGrid link, a legitimate customer communication service used by marketing professionals. SendGrid links are commonly used in phishing attacks, as they require minimal effort.

Figure 3: Phishing Page, Step 1

Upon clicking the SendGrid link, the user is redirected to a phishing page, as seen in Figure 3. The only difference between a legitimate WebEx login page and this phishing page is the URL itself, suggesting the attacker conducted some form of web scraping to create an intentionally benign looking and familiar login page for the end user. Web scraping, essentially, is the practice of using a tool to automatically copy data from a website and create a convincing copy.

Figure 4: Phishing Page, Step 2

Deception quickly falls apart when reviewing the URL, however; while designed to look like the actual URL, there actually isn’t a portion that includes ‘webex.com’. The numerous dashes, coupled with one very long word followed by ‘index.php’ is not reflective of a professional link, suggesting the phishing URL was registered to appear legitimate at first glance. While phishers commonly make a valiant effort for their pages to look legitimate, looking at the address bar generally reveals if it’s legitimate. Misspelling, similar looking words and strange top-level domains are common tricks used by attackers to guile end users for just long enough to not question it.

While the initial phishing page only requests the user’s email address, the following page then changes URLs from “index.php” to “step2.php” and asks for the user’s password- this is another indicator the site is not legitimate, as the specific internals of which php file is being invoked for this webpage would be usually be hidden to the user.

Figure 5: Final redirect to official WebEx login page

As the final stage of attack, when the user enters their credentials on the page shown in Figure 5 above, the user is then redirected to WebEx’s real sign-in page. At this point, the malicious actor now has the user’s credentials, but it is in their best interest to ensure the user is unaware that a successful credential phishing attack occurred, giving the threat actors time to make use of newly stolen log-in details. The final redirect to WebEx’s legitimate log-in page may make the end user believe there was a log-in error and they need to log-in again. A common theme in a many phishing attacks is appealing to and preying on the feeling that nothing is amiss and there is nothing to question about the experience. In the meantime, threat actors gain precious time to do damage while the end user moves on with his or her workday.

Figure 6: Open Directory

A final interesting finding about this phishing campaign is the main domain itself, which reveals an open directory. This open directory shows the files included in the phishing page: images, fonts, .css files, and more. Although finding this directory was easy, it isn’t necessary to hide it, as most end users will only go through to login rather investigating into the internals of the site. However, it must be noted no professional website allows access to its file directories in this way. If reached, it is an almost sure-fire way of immediately identifying a phish.

Network IOC IP
hXXps://cert-ssl-global-prod-webmeetings[.]com/da4njy=/idb/saml/jsp/index[.]php 137[.]135[.]110[.]140

 

How Cofense Can Help

Visit Cofense’s Remote Work Phishing Infocenter to stay up to date as threats evolve. Our site is updated with screenshots and YARA rules as we continue to track campaigns.

All third-party trademarks referenced by Cofense whether in logo form, name form or product form, or otherwise, remain the property of their respective holders, and use of these trademarks in no way indicates any relationship between Cofense and the holders of the trademarks. Any observations contained in this blog regarding circumvention of end point protections are based on observations at a point in time based on a specific set of system configurations. Subsequent updates or different configurations may be effective at stopping these or similar threats.
The Cofense® and PhishMe® names and logos, as well as any other Cofense product or service names or logos displayed on this blog are registered trademarks or trademarks of Cofense Inc.