This vulnerability (CVE-2026-62918) in Microsoft Teams is classified under CWE-347, indicating improper verification of cryptographic signatures. The flaw enables an attacker without privileges or user interaction to spoof communications by exploiting the signature verification process. The CVSS 3.1 base score is 7.5, reflecting network attack vector, low attack complexity, no privileges required, no user interaction, unchanged scope, no confidentiality impact, high integrity impact, and no availability impact. Microsoft has published an official fix to remediate this vulnerability.

An attacker can spoof communications within Microsoft Teams by exploiting improper cryptographic signature verification, potentially misleading users or systems relying on signature authenticity. There is no direct impact on confidentiality or availability, but the integrity of messages or data can be compromised.

An official fix is available from Microsoft. Users and administrators should apply the vendor-provided patch as soon as possible to remediate this vulnerability. Refer to the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62918 for detailed update instructions.