CVE-2026-55946: Microsoft Copilot Information Disclosure Vulnerability

Medium severity · published Sep 17, 2026

CVE-2026-55946

Microsoft Copilot Information Disclosure Vulnerability

5.9

CVSS

0.4%

EPSS

On KEV

Description

Ai command injection in Microsoft Copilot allows an unauthorized attacker to disclose information over a network.

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack vector

Network

Complexity

High

Privileges

None

User interaction

None

Confidentiality

High

Integrity

None

Availability

None

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)0.4% · higher than 33% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

Microsoft Copilot · Microsoft

All versions, or not specified · source: vendor

Copilot · Microsoft

All versions, or not specified · source: NVD

Affected product

Microsoft Copilot

Microsoft

All Microsoft Copilot CVEs

References

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-55946

CVE.org

https://www.cve.org/CVERecord?id=CVE-2026-55946

vendor-advisory

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55946