CVE-2026-69646: CWE-347: Improper Verification of Cryptographic Signature in Microsoft Skype for Business Server 2015 CU13
CVE-2026-69646 is a high-severity vulnerability in Microsoft Skype for Business Server 2015 CU13 (build 9319.0) involving improper verification of cryptographic signatures. This flaw allows an unauthorized attacker on an adjacent network to perform spoofing attacks. An official fix is available from Microsoft to address this issue.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-69646) is classified under CWE-347, indicating improper verification of cryptographic signatures in Microsoft Skype for Business Server 2015 CU13. The flaw enables an attacker with network adjacency to spoof communications by exploiting the signature verification weakness. The CVSS 3.1 base score is 8.3, reflecting high impact on confidentiality, integrity, and low impact on availability. Microsoft has released an official fix to remediate this vulnerability.
Potential Impact
Successful exploitation allows an attacker on an adjacent network to spoof communications within Skype for Business Server 2015 CU13, potentially compromising confidentiality and integrity of communications. Availability impact is low. There are no known exploits in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69646 to remediate this vulnerability.
CVE-2026-69646: CWE-347: Improper Verification of Cryptographic Signature in Microsoft Skype for Business Server 2015 CU13
Description
CVE-2026-69646 is a high-severity vulnerability in Microsoft Skype for Business Server 2015 CU13 (build 9319.0) involving improper verification of cryptographic signatures. This flaw allows an unauthorized attacker on an adjacent network to perform spoofing attacks. An official fix is available from Microsoft to address this issue.
CVSS v3.1
Score 8.3high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-69646) is classified under CWE-347, indicating improper verification of cryptographic signatures in Microsoft Skype for Business Server 2015 CU13. The flaw enables an attacker with network adjacency to spoof communications by exploiting the signature verification weakness. The CVSS 3.1 base score is 8.3, reflecting high impact on confidentiality, integrity, and low impact on availability. Microsoft has released an official fix to remediate this vulnerability.
Potential Impact
Successful exploitation allows an attacker on an adjacent network to spoof communications within Skype for Business Server 2015 CU13, potentially compromising confidentiality and integrity of communications. Availability impact is low. There are no known exploits in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69646 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-08-03T21:24:59.409Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69646","vendor":"Microsoft"}]
Threat ID: 6aa059e3acd9273b4913eacc
Added to database: 09/08/2026, 18:54:27 UTC
Last enriched: 09/08/2026, 19:07:05 UTC
Last updated: 09/08/2026, 19:45:52 UTC
Views: 4
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