CVE-2026-26143: CWE-20: Improper Input Validation in Microsoft PowerShell 7.4
Improper input validation in Microsoft PowerShell allows an unauthorized attacker to bypass a security feature locally.
AI Analysis
Technical Summary
This vulnerability in Microsoft PowerShell 7.4.0 involves improper input validation (CWE-20) that enables a local attacker without privileges to bypass security controls. The CVSS 3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability. The vulnerability requires local access and user interaction but has low attack complexity and no privileges required. Microsoft has published an official fix to remediate this issue.
Potential Impact
Successful exploitation can lead to bypassing security features locally, resulting in complete compromise of confidentiality, integrity, and availability of the affected system. The vulnerability does not require privileges but does require user interaction and local access.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26143 to remediate this vulnerability.
CVE-2026-26143: CWE-20: Improper Input Validation in Microsoft PowerShell 7.4
Description
Improper input validation in Microsoft PowerShell allows an unauthorized attacker to bypass a security feature locally.
CVSS v3.1
Score 7.8high
Affected software
pkg:github/powershell/powershellRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in Microsoft PowerShell 7.4.0 involves improper input validation (CWE-20) that enables a local attacker without privileges to bypass security controls. The CVSS 3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability. The vulnerability requires local access and user interaction but has low attack complexity and no privileges required. Microsoft has published an official fix to remediate this issue.
Potential Impact
Successful exploitation can lead to bypassing security features locally, resulting in complete compromise of confidentiality, integrity, and availability of the affected system. The vulnerability does not require privileges but does require user interaction and local access.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26143 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-02-11T16:24:51.134Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26143","vendor":"Microsoft"}]
Threat ID: 69de7a1682d89c981fd6a624
Added to database: 04/14/2026, 17:32:06 UTC
Last enriched: 06/19/2026, 16:57:49 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 130
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