Microsoft Windows is affected by CVE-2026-96951, rated 8.8 (high). CISA lists it as a Known Exploited Vulnerability, added on 2026-10-13, which means attacks against it have been observed.

What the flaw is

The NIST National Vulnerability Database describes it as follows:

Improper neutralization of special elements used in a command ('command injection') in Windows Shell allows an unauthorized attacker to bypass a security feature over a network.

At a glance

FieldDetail
CVECVE-2026-96951
Affected productMicrosoft Windows
WeaknessCWE-77 (Command Injection)
CVSS8.8 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Added to CISA KEV2026-10-13
Federal remediation due2026-10-16
Known ransomware useUnknown

What defenders should do

  • CISA required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
  • Patch: apply the fixed release from Microsoft; check the vendor advisory linked below for the exact versions.
  • Inventory: identify every instance of Microsoft Windows, prioritising internet-facing ones.
  • Hunt: review access and application logs on exposed instances for activity predating the patch, and treat unpatched internet-facing instances as potentially compromised.