CVE-2026-66303: CWE-476: NULL Pointer Dereference in Microsoft Skype for Business Server 2015 CU13
Null pointer dereference in Skype for Business allows an authorized attacker to deny service over a network.
AI Analysis
Technical Summary
This vulnerability, identified as CWE-476 (NULL Pointer Dereference), exists in Microsoft Skype for Business Server 2015 CU13 version 9319.0. It allows an attacker with authorized access to trigger a null pointer dereference condition, resulting in denial of service. The CVSS 3.1 base score is 6.5, indicating a medium severity impact primarily due to availability loss. Microsoft has issued an official fix for this vulnerability, as documented in their security update guide.
Potential Impact
An authorized attacker can exploit this vulnerability to cause a denial of service condition on the affected Skype for Business Server, disrupting service availability. There is no impact on confidentiality or integrity according to the CVSS vector. No known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Administrators should apply the security update provided by Microsoft for Skype for Business Server 2015 CU13 version 9319.0 to remediate this vulnerability.
CVE-2026-66303: CWE-476: NULL Pointer Dereference in Microsoft Skype for Business Server 2015 CU13
Description
Null pointer dereference in Skype for Business allows an authorized attacker to deny service over a network.
CVSS v3.1
Score 6.5medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, identified as CWE-476 (NULL Pointer Dereference), exists in Microsoft Skype for Business Server 2015 CU13 version 9319.0. It allows an attacker with authorized access to trigger a null pointer dereference condition, resulting in denial of service. The CVSS 3.1 base score is 6.5, indicating a medium severity impact primarily due to availability loss. Microsoft has issued an official fix for this vulnerability, as documented in their security update guide.
Potential Impact
An authorized attacker can exploit this vulnerability to cause a denial of service condition on the affected Skype for Business Server, disrupting service availability. There is no impact on confidentiality or integrity according to the CVSS vector. No known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Administrators should apply the security update provided by Microsoft for Skype for Business Server 2015 CU13 version 9319.0 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-07-24T18:06:51.294Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66303","vendor":"Microsoft"}]
Threat ID: 6aa059e1acd9273b4913b7f2
Added to database: 09/08/2026, 18:54:25 UTC
Last enriched: 09/08/2026, 19:08:08 UTC
Last updated: 09/09/2026, 01:35:57 UTC
Views: 9
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