CVE-2026-70338: Microsoft PowerShell Security Feature Bypass Vulnerability

highCVSS 7.8CVE-2026-70338

Improper control of generation of code ('code injection') in Microsoft PowerShell allows an unauthorized attacker to bypass a security feature locally.

CSIRTS triage

vendor: Microsoft product: PowerShell Code injection Authentication bypass

What: Code injection vulnerability in PowerShell allows bypass of security features locally.
Who is affected: Windows systems with PowerShell installed that execute untrusted scripts or commands.
Urgency: High severity; security feature bypasses require prompt remediation despite no current active exploitation.
Action: Apply the latest Microsoft PowerShell security update as soon as available.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 7.8
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70338

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-703380.34% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 26% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-70338	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.