SB2026011492 - Multiple vulnerabilities in Microsoft Windows File Explorer
Published: January 14, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 vulnerabilities.
1) Information disclosure (CVE-ID: CVE-2026-20939)
CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists due to excessive data output by the application in Windows File Explorer. A local user can gain unauthorized access to sensitive information on the system.
2) Information disclosure (CVE-ID: CVE-2026-20823)
CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists due to excessive data output by the application in Windows File Explorer. A local user can gain unauthorized access to sensitive information on the system.
3) Information disclosure (CVE-ID: CVE-2026-20932)
CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists due to excessive data output by the application in Windows File Explorer. A local user can gain unauthorized access to sensitive information on the system.
4) Race condition (CVE-ID: CVE-2026-20808)
CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a race condition in Windows File Explorer. A local user can exploit the race and escalate privileges on the system.
5) Information disclosure (CVE-ID: CVE-2026-20937)
CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists due to excessive data output by the application in Windows File Explorer. A local user can gain unauthorized access to sensitive information on the system.
Remediation
Install update from vendor's website.
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20939
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20823
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20932
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20808
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20937