Microsoft Security Response Center guidance
Vendor revision: Sep 8, 2026Install KB5123300. Install KB5123287. Install KB5123301.
Vulnerability intelligence
CVE-2026-66302 and is rated Critical severity with a CVSS score of 9.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
Install KB5123300. Install KB5123287. Install KB5123301.
External control of file name or path in Skype for Business allows an unauthorized attacker to execute code over a network.
Source: NVD