CVE-2026-69646: Skype for Business Spoofing Vulnerability
Improper verification of cryptographic signature in Skype for Business allows an unauthorized attacker to perform spoofing over an adjacent network.
Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69646
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-69646 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
Recent advisories for Skype for Business
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- highCVE-2026-69646: Improper verification of cryptographic signature in Skype for Business allows an unauthorized …nvd · 2026-09-08
- mediumCVE-2026-69642: Improper neutralization of input during web page generation ('cross-site scripting') in Skype …nvd · 2026-09-08
- mediumCVE-2026-66308: Out-of-bounds read in Skype for Business allows an authorized attacker to deny service over a …nvd · 2026-09-08
- highCVE-2026-66307: Integer underflow (wrap or wraparound) in Skype for Business allows an unauthorized attacker t…nvd · 2026-09-08
- mediumCVE-2026-66306: Generation of error message containing sensitive information in Skype for Business allows an u…nvd · 2026-09-08
- highCVE-2026-66305: Use of client-side authentication in Skype for Business allows an authorized attacker to perfo…nvd · 2026-09-08
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