New research by Check Point Research has revealed critical vulnerabilities in Microsoft Teams that highlight a crucial lesson for businesses: trust alone is not a security strategy. These flaws could allow attackers to impersonate executives, manipulate messages, spoof notifications, and compromise sensitive communications across organizations.
With over 320 million monthly active users, Microsoft Teams is a cornerstone of modern workplace communication. From corporate meetings to quick one-on-one chats, it drives daily operations for enterprises, small businesses, and governments worldwide. However, Check Point Research’s findings demonstrate how cyber attackers can exploit the very trust mechanisms that make Teams effective, turning collaboration into a potential attack vector.
Microsoft Teams is widely used across industries, so its customer base includes large enterprises, educational institutions, and government organizations. Some well-known organizations that use Microsoft Teams include: Accenture, Coca-Cola, Lufthansa, General Motors (GM), SAP, University of Cambridge, NASA, Adobe, Walgreens and Heathrow Airport.
Collaboration Apps as the New Attack Surface
In recent years, cyber attackers have heavily targeted email as a primary communication channel. Today, that same strategy is shifting to collaboration platforms like Microsoft Teams, Slack, and Zoom. These tools are no longer just productivity enablers—they are mission-critical business infrastructure.
Sophisticated threat actors, including advanced persistent threat (APT) groups and financially motivated cybercriminals, have recognized that manipulating trusted communication channels allows them to bypass conventional defenses. Social engineering thrives in environments of trust, and collaboration platforms are built on trust.
Key Vulnerabilities in Microsoft Teams
Check Point Research identified multiple flaws affecting both external guests and malicious insiders. Key vulnerabilities include:
Invisible Message Editing: Attackers could silently alter previously sent messages without triggering the “Edited” label, undermining trust in historical conversations.
Spoofed Notifications: Manipulated notifications can appear to come from trusted executives or colleagues, prompting users to act on fraudulent alerts.
Altering Display Names via Conversation Topics: By modifying conversation topics in private chats, attackers could mislead participants about the context of their discussions.
Forged Caller Identity in Video/Audio Calls: Attackers could change the display name in call notifications, allowing them to impersonate any colleague during calls.
Microsoft has addressed these vulnerabilities with updates throughout 2024 and 2025, ensuring that users need not take any action. Still, the incidents reveal a deeper risk: the exploitation of digital trust itself.
Implications for Businesses
The Teams vulnerabilities show that collaboration apps are a prime target for manipulation. Unlike technical exploits that break encryption, these attacks work by subverting trust signals—notifications, display names, and quoted messages—all subtle cues employees rely on. Compromising these can influence decision-making, enable fraud, deliver malware, or spread misinformation.
A Broader Trend Across Platforms
Microsoft Teams is not unique. Check Point Research has identified similar flaws in other collaboration tools, workflow automation platforms, and AI-driven assistants. Wherever digital trust exists, attackers are probing for weaknesses.
Mitigation: Adopting a Layered Security Approach
Organizations must go beyond relying solely on platform trust. Check Point recommends a multi-layered defense strategy:
Malware and File Protection: Prevent malicious files, links, and payloads from spreading through collaboration tools.
Data Loss Prevention (DLP): Secure sensitive business information as it moves across chats and shared files.
Threat Detection and Response: Monitor for unusual behavior, such as spoofed sessions or manipulated messages.
Unified Protection Across Apps: Extend security beyond collaboration platforms to email, browsers, and other digital workflows.
Microsoft Teams vulnerabilities are a wake-up call for organizations worldwide. Attackers are no longer just breaking into systems—they are breaking into conversations. As collaboration tools become central to business operations, organizations must recognize the limits of trust and implement robust, layered security measures to safeguard communications and decision-making.
Rajani Baburajan
