This vulnerability (CWE-862) in Microsoft Teams is caused by missing authorization checks, enabling an attacker to gain elevated privileges remotely without requiring user interaction. The CVSS 3.1 vector indicates network attack vector, low attack complexity, no privileges required, no user interaction, scope changed, and high impact on confidentiality and integrity. Microsoft has published an official fix to remediate this vulnerability.

Successful exploitation allows an attacker to elevate privileges over the network, potentially gaining unauthorized access to sensitive information and control within Microsoft Teams. The vulnerability does not affect availability. The critical CVSS score reflects the high impact on confidentiality and integrity.

An official fix is available from Microsoft. Users and administrators should apply the provided patch promptly. Refer to the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-65667 for detailed remediation instructions.