Microsoft Teams, one of the world’s most widely used collaboration platforms, has recently come under scrutiny after cybersecurity researchers discovered four serious vulnerabilities that could allow attackers to impersonate colleagues and alter chat messages without detection. These flaws, if exploited, could enable large-scale social engineering attacks that put corporate communications and sensitive information at risk.
According to a detailed report by Check Point Research, the vulnerabilities allowed attackers to manipulate conversations, change message content, and even forge sender identities within Microsoft Teams. This could make malicious messages appear as if they were coming from trusted co-workers or executives, increasing the chances of users falling for phishing or malware traps.
The discovered flaws impacted both internal users and external guests, creating opportunities for cybercriminals to cross company boundaries and trick unsuspecting employees. Attackers could change the sender’s name, alter message content without triggering the “Edited” tag, and modify notifications to disguise who actually sent a message.
In simple terms, a hacker could send a malicious message that looks completely legitimate—say, from a CEO or IT administrator—without leaving any signs of tampering. This type of attack exploits human trust, the very foundation of digital collaboration tools like Teams.
Researchers also found that attackers could manipulate private chat display names by editing the conversation topic. In addition, they could modify caller identities in call notifications and during live calls, making it appear as though a legitimate contact was reaching out. These manipulations could lead victims to unknowingly share confidential information or click on harmful links.
Check Point reported these issues to Microsoft in March 2024 as part of a responsible disclosure process. Microsoft began addressing the flaws in August 2024, assigning one of the key vulnerabilities the identifier CVE-2024-38197. This particular flaw has been classified as a medium-severity spoofing issue with a CVSS score of 6.5, affecting Microsoft Teams for iOS.
Additional patches were rolled out in September 2024 and October 2025, closing off the loopholes that made these attacks possible. However, experts warn that these kinds of flaws highlight the ongoing challenges of securing collaboration platforms, especially those used by millions of employees worldwide.
Microsoft Teams has become a critical communication hub for organizations across the globe, especially in the era of hybrid and remote work. As such, any flaw that undermines message authenticity poses a direct threat to business trust and data security.
Oded Vanunu, Head of Product Vulnerability Research at Check Point, emphasized the larger implications:
“These vulnerabilities hit at the heart of digital trust. Collaboration platforms like Teams are now as critical as email and just as exposed.”
He further added that cybercriminals don’t always need to “break in” anymore—they simply need to bend trust. In other words, attackers can exploit human perception instead of technical weaknesses, using social engineering as their primary weapon.
In recent years, cybercriminals and even state-sponsored threat actors have increasingly targeted collaboration platforms like Microsoft Teams, Slack, and Zoom. These tools, once seen as convenient work enablers, have now become high-value targets for exploitation.
According to Microsoft’s own advisory, Teams’ extensive features—chat, calls, video meetings, and screen sharing—can be weaponized at multiple stages of an attack. Threat actors often use fake support messages, malicious file shares, or deceptive links to convince users to grant remote access or run harmful scripts.
Because such interactions happen within trusted corporate environments, employees are far more likely to believe the messages are legitimate. That’s why attackers exploiting these vulnerabilities could easily bypass even well-trained security-conscious users.
To safeguard against future exploitation, experts recommend organizations take several proactive steps:
Keep Teams and Microsoft 365 apps updated – Ensure all patches, especially those addressing CVE-2024-38197, are applied promptly.
Enable multi-factor authentication (MFA) – Adds an extra layer of protection against account hijacking.
Use strict guest access policies – Limit permissions for external users to reduce attack surfaces.
Educate employees – Conduct regular awareness training to help users recognize suspicious messages, calls, or links—even if they appear to come from trusted colleagues.
Monitor for unusual activity – Security teams should actively look for anomalies in chat logs or message behavior.
The recent Microsoft Teams vulnerabilities are a stark reminder that trust can be weaponized. As organizations increasingly depend on collaboration tools for daily operations, attackers are shifting focus from breaking into systems to breaking human confidence.
While Microsoft has patched the known flaws, the incident underscores the importance of constant vigilance, layered defenses, and user awareness. In the digital workplace, “seeing” a trusted name is no longer enough—verification is essential.
Interesting Article : CVE-2025-5397, Hackers Exploit Jobmonster WordPress Theme to Gain Admin Access
Pingback: CVE-2025-21042: Samsung Zero-Day Exploited to Deploy LANDFALL Spyware