Wednesday, February 21, 2024

Hackers Hijack Microsoft Teams Accounts Using a Single Weaponized GIF Image

Microsoft has patched a subdomain takeover vulnerability in Microsoft Teams that affects every user who uses the Teams desktop or web browser version.

Microsoft Teams is a leading communication and collaboration platform that combines workplace features such as chat, video meetings, file storage, collaboration on files, and integration with applications.

Microsoft Teams Vulnerability

Researchers from CyberArk discovered a worm-like vulnerability that lets hackers use a malicious GIF file to scrape user data and to take over the entire roster of Teams accounts.

The vulnerability resides in how the application programming interfaces (APIs) used to validate the communication between the client and the server.

With Teams access token (auth token) and the skype token is used to make API calls that let users send messages, read messages, create groups, add new users or remove users from groups, change permissions in groups, etc.

Microsoft Teams

According to CyberArk, the following subdomains are vulnerable to takeover;


An attacker can force the user to visit one of the sub-domains and get access to the auth token, by having the auth token attackers can steal the victim’s Teams account data.

“We considered this approach as well, sending an image to our victim with an “src” attribute set to the compromised sub-domain via Teams chat. When the victim opens this message, the victim’s browser will try to load the image and this will send the auth token cookie to the compromised sub-domain, “reads Cyberark blog post.

Victims will not have any indication of they’ve been attacked as the take over process is stealthy and dangerous.

Researchers published a video POC exploit of the vulnerability, they also warned that the vulnerability is wormable.

The vulnerability has been reported by Microsoft Security Research Center and Microsoft fixed the vulnerability by deleting the misconfigured DNS records of the two subdomains.

A Couple of days before a new Zoom flaw lets hackers record Zoom meeting sessions and to capture the chat text without the knowledge of meeting participants’ even though host disables recording option for the participants.

Due to this COVID-19 pandemic situation, many companies moved to full-time remote work, vulnerabilities like this may pose a huge risk.

You can follow us on LinkedinTwitterFacebook for daily Cybersecurity and hacking news updates.


Latest articles

Beware of VietCredCare Malware that Steals businesses’ Facebook Accounts

A new cybersecurity threat targeting Facebook advertisers in Vietnam, known as VietCredCare, has emerged....

Google Chrome 122 Update Addresses Critical Security Vulnerabilities

Google has recently unveiled Chrome 122, a significant milestone for the widely used web...

New Malicious PyPI Packages Use DLL Sideloading In A Supply Chain Attack

Researchers have discovered that threat actors have been using open-source platforms and codes for...

New Mingo Malware Attacking Linux Redis Servers To Mine Cryptocurrency

The malware, termed Migo by the creators, attempts to infiltrate Redis servers to mine cryptocurrency on...

Security Onion 2.4.50 Released for Defenders With New Features

Security Onion Solutions has recently rolled out the latest version of its network security...

VMware Urges to Remove Enhanced EAP Plugin to Stop Auth & Session Hijack Attacks

VMware has issued an urgent advisory to administrators to remove a deprecated authentication plugin...

LockBit Ransomware Members Charged by Authorities, Free Decryptor Released

In a significant blow to one of the most prolific ransomware operations, authorities from...
Guru baran
Guru baran
Gurubaran is a co-founder of Cyber Security News and GBHackers On Security. He has 10+ years of experience as a Security Consultant, Editor, and Analyst in cybersecurity, technology, and communications.

Live Account Takeover Attack Simulation

Live Account Take Over Attack

Live Webinar on How do hackers bypass 2FA ,Detecting ATO attacks, A demo of credential stuffing, brute force and session jacking-based ATO attacks, Identifying attacks with behaviour-based analysis and Building custom protection for applications and APIs.

Related Articles