What is CVE-2026-55946?

CVE-2026-55946 is a medium-severity vulnerability in Microsoft Copilot, classified under Command Injection. CVSS score: 6.1/10. Published 2026-09-17.

How severe is CVE-2026-55946?

Medium severity. CVSS v3 base score is 6.1 out of 10.

RCE in Microsoft Copilot

CVE-2026-55946

Improper neutralization of special elements used in a command ('command injection') in Microsoft Copilot allows an unauthorized attacker to disclose information over a network.

Vulnerability class: Command Injection (OS Command Injection)

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:N/A:N.

Affected products

Microsoft Copilot

Weakness classification (CWE)

CWE-77 — Command Injection

References

secure@microsoft.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-55946?: CVE-2026-55946 is a medium-severity vulnerability in Microsoft Copilot, classified under Command Injection. CVSS score: 6.1/10. Published 2026-09-17.
How severe is CVE-2026-55946?: Medium severity. CVSS v3 base score is 6.1 out of 10.