CVE-2026-26143 Microsoft CVE debrief

Who should care

Defenders responsible for PowerShell deployments, particularly those using PowerShell 7.4 and 7.5, should assess exposure and prioritize updates.

Why it matters

The vulnerability allows unauthorized attackers to bypass a security feature locally, potentially leading to security risks in PowerShell deployments.

• Verify and update PowerShell deployments to prevent local security feature bypass
• Implement secure input validation to prevent unauthorized access

Technical summary

The vulnerability is caused by improper input validation in Microsoft PowerShell, allowing unauthorized attackers to bypass a security feature locally. This could potentially lead to security risks in PowerShell deployments if not addressed. The vulnerability affects PowerShell deployments, particularly those using PowerShell 7.4 and 7.5. Defenders should assess exposure and prioritize updates to prevent local security feature bypass.

Defensive priority

Defenders should prioritize verifying and updating PowerShell 7.4 and 7.5 to the latest versions, as the vulnerability allows local security feature bypass.

Recommended defensive actions

• Verify and update PowerShell 7.4 and 7.5 to the latest versions
• Review and implement secure input validation for PowerShell
• Monitor for potential local security feature bypass attempts

Evidence notes

The CVE record and source item provide details on the vulnerability, but limited information is available on exploitation or impact. Defenders should verify and update PowerShell 7.4 and 7.5 to the latest versions and review secure input validation practices. The vulnerability allows unauthorized attackers to bypass a security feature locally, potentially leading to security risks in PowerShell deployments. There is no information on public exploitation, but defenders should prioritize

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.