Microsoft Teams spoofing vulnerabilities disclosed by Check Point Research, including CVE-2024-38197, reveal how attackers could impersonate executives, manipulate messages, and forge caller identities inside a platform used by more than 320 million people. The research shows that both external guests and malicious insiders were able to edit messages without leaving an “Edited” label, alter notifications to appear as if they came from high-profile users, and change conversation topics such that private chats displayed misleading participant names. Additionally, crafted call initiation requests let adversaries arbitrarily modify the displayName field, making video and audio call notifications appear to originate from any chosen identity. Microsoft Teams spoofing flaws have now been patched by Microsoft, but their exploitation paths highlight systemic weaknesses in collaboration tool trust models. By forging message senders and caller identities, attackers could drive convincing business email compromise–style fraud, social engineering, and misinformation campaigns entirely within Teams. Scenarios include fake payment authorization messages from CFO accounts, spoofed incident coordination calls, or manipulated chat histories used to discredit employees or mask prior instructions. Because users tend to treat internal collaboration notifications as inherently trustworthy, these vulnerabilities magnified the impact of stolen credentials or compromised bot integrations. Microsoft Teams spoofing mitigation extends beyond simply applying the fixes for CVE-2024-38197 and related bugs. Organizations must reassess how much inherent trust they grant to collaboration channels, enforce strong MFA and conditional access for Teams accounts, and implement behavioral monitoring that can flag unusual notification patterns or identity changes. User education should emphasize out-of-band verification for high-risk requests, especially financial approvals and credential-sharing prompts, recognizing that even familiar avatars and display names can be forged when platform-side validation controls are weak or bypassed.
🎯CORTEX Protocol Intelligence Assessment
Business Impact: Microsoft Teams spoofing issues undermine the integrity of internal communications that drive approvals, incident response, and executive coordination. Exploitation could lead to fraudulent payments, data leakage, and reputational damage as employees act on instructions they believe originated from trusted senior leaders or colleagues. Technical Context: The vulnerabilities abused weak validation of sender fields, notification metadata, and call participant attributes, enabling both external guests and insider adversaries to rewrite how identities appeared across chats and calls. Even though Microsoft has issued patches, the research underscores the need for robust identity verification, telemetry-based anomaly detection, and skepticism toward high-value requests delivered solely via collaboration platforms.
⚡Strategic Intelligence Guidance
- Verify that all Microsoft Teams clients and tenants have applied the fixes associated with CVE-2024-38197 and any related spoofing vulnerabilities, prioritizing mobile and web clients used by executives.
- Strengthen identity protections for Teams by enforcing phishing-resistant MFA, conditional access policies, and device compliance checks for high-privilege accounts.
- Implement training and executive briefings that promote out-of-band verification for sensitive actions initiated via Teams, particularly around payments, credential sharing, and access approvals.
- Integrate collaboration platform telemetry into SIEM and UEBA solutions, building detections for unusual patterns such as unexpected topic changes, impersonation-like displayName usage, or anomalous bot activity.
Vendors
Microsoft TeamsCheck Point
Threats
Notification spoofingExecutive impersonation
Targets
Teams usersExecutives and finance staffRemote workforce