CVE-2026-20839: CWE-284: Improper Access Control in Microsoft Windows 10 Version 1607
Improper access control in Windows Client-Side Caching (CSC) Service allows an authorized attacker to disclose information locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-20839) affects Windows 10 Version 1607 (build 10.0.14393.0) and stems from improper access control in the Windows Client-Side Caching (CSC) Service. An attacker with local authorized privileges can exploit this flaw to disclose sensitive information locally. The vulnerability does not affect integrity or availability and does not require user interaction. The CVSS 3.1 vector indicates low attack complexity and privileges required, with a high impact on confidentiality. A patch is available from Microsoft to remediate this issue.
Potential Impact
An authorized local attacker can disclose sensitive information due to improper access control in the CSC Service. This impacts confidentiality but does not affect system integrity or availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
A patch is available to address this vulnerability. It is recommended to apply the official Microsoft update for Windows 10 Version 1607 (build 10.0.14393.0) to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-20839: CWE-284: Improper Access Control in Microsoft Windows 10 Version 1607
Description
Improper access control in Windows Client-Side Caching (CSC) Service allows an authorized attacker to disclose information locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-20839) affects Windows 10 Version 1607 (build 10.0.14393.0) and stems from improper access control in the Windows Client-Side Caching (CSC) Service. An attacker with local authorized privileges can exploit this flaw to disclose sensitive information locally. The vulnerability does not affect integrity or availability and does not require user interaction. The CVSS 3.1 vector indicates low attack complexity and privileges required, with a high impact on confidentiality. A patch is available from Microsoft to remediate this issue.
Potential Impact
An authorized local attacker can disclose sensitive information due to improper access control in the CSC Service. This impacts confidentiality but does not affect system integrity or availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
A patch is available to address this vulnerability. It is recommended to apply the official Microsoft update for Windows 10 Version 1607 (build 10.0.14393.0) to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-03T05:54:20.376Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69668adea60475309f9ae097
Added to database: 1/13/2026, 6:11:42 PM
Last enriched: 4/3/2026, 12:44:33 PM
Last updated: 5/8/2026, 9:19:46 PM
Views: 192
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