Microsoft Teams Vulnerabilities Exposed: Impersonation and Message Tampering Risks Revealed

Recent cybersecurity research has uncovered significant security flaws within Microsoft Teams, potentially allowing attackers to impersonate colleagues and alter messages without detection. These vulnerabilities undermine the trust inherent in collaboration platforms, turning a business enabler into a tool for deception and social engineering.

Key Takeaways

• Four security flaws in Microsoft Teams have been disclosed.

• These flaws enable attackers to impersonate colleagues and edit messages unnoticed.

• Vulnerabilities could lead to social engineering attacks, tricking users into clicking malicious links or sharing sensitive data.

• Microsoft has released patches for some of these issues, with ongoing remediation efforts.

Exploiting Trust in Collaboration

Cybersecurity firm Check Point has detailed four vulnerabilities in Microsoft Teams that could expose users to serious impersonation and social engineering attacks. These shortcomings allowed attackers to manipulate conversations, impersonate colleagues, and alter incoming notifications to appear as if they originated from a trusted source, including high-ranking executives. This could trick unsuspecting victims into opening malicious messages or sharing sensitive information.

The vulnerabilities affect both external guest users and internal malicious actors, posing a significant risk by eroding security boundaries. The ability to alter message content without the "Edited" label and to forge sender identities in notifications and calls presents a grave threat to digital trust.

Patching and Ongoing Efforts

Following responsible disclosure in March 2024, Microsoft began addressing these issues. Some vulnerabilities were patched in August 2024, with further updates released in September 2024 and October 2025. One notable vulnerability, CVE-2024-38197, a medium-severity spoofing issue affecting Teams for iOS, allowed attackers to alter sender names, potentially leading to social engineering ploys.

Microsoft acknowledges that the extensive collaboration features and widespread adoption of Teams make it a prime target for cybercriminals and state-sponsored actors. The company's messaging, calls, meetings, and screen-sharing features are being weaponized at various stages of attack chains.

The Erosion of Digital Trust

Oded Vanunu, head of product vulnerability research at Check Point, emphasized that these vulnerabilities strike at the core of digital trust. He stated that collaboration platforms are now as critical and exposed as email, and that threat actors are increasingly exploiting trust rather than breaking into systems. Organizations are urged to focus on verifying information rather than solely relying on perceived authenticity, as "seeing isn't believing anymore, verification is."

As cyber threats become increasingly sophisticated, your security strategy must evolve to keep pace. BetterWorld Technology offers adaptive cybersecurity solutions that grow with the threat landscape, helping your business stay secure while continuing to innovate. Reach out today to schedule your personalized consultation.

Sources

• Microsoft Teams Bugs Let Attackers Impersonate Colleagues and Edit Messages Unnoticed, The Hacker News.