What is CVE-2026-26143?

CVE-2026-26143 is a high-severity vulnerability in Microsoft Powershell 7.4, classified under Improper Input Validation. CVSS score: 7.8/10. Published 2026-04-14.

How severe is CVE-2026-26143?

High severity. CVSS v3 base score is 7.8 out of 10.

Improper input validation in Microsoft Powershell 7.4

CVE-2026-26143

Improper input validation in Microsoft PowerShell allows an unauthorized attacker to bypass a security feature locally.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.001 (18.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C.

Affected products

Microsoft Powershell 7.4 — versions 7.4.0
Microsoft Powershell 7.5 — versions 7.5.0

Weakness classification (CWE)

CWE-20 — Improper Input Validation

References

Microsoft PowerShell Security Feature Bypass Vulnerability (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-26143?: CVE-2026-26143 is a high-severity vulnerability in Microsoft Powershell 7.4, classified under Improper Input Validation. CVSS score: 7.8/10. Published 2026-04-14.
How severe is CVE-2026-26143?: High severity. CVSS v3 base score is 7.8 out of 10.