CVE-2026-41090: Microsoft Copilot Command Injection Vulnerability
CVE-2026-41090 is a command injection weakness (CWE-77) in Microsoft Copilot that the CNA describes as allowing an unauthorized attacker to perform tampering over a network. The CNA-supplied CVSS score is 9.3 with a critical severity rating. The sources consulted do not list active exploitation, and the record provides no fixed versions.
Overview
CVE-2026-41090 affects Microsoft Copilot and is classified as command injection (CWE-77). The CNA description states that an unauthorized attacker can perform tampering over a network. The primary reference is the Microsoft Security Response Center advisory.
Impact
- The CNA-supplied CVSS vector indicates high confidentiality impact and high integrity impact, with no availability impact.
- The vector also indicates that no privileges are required and that user interaction is required, and that the scope is changed.
- The SSVC data in the record reports total technical impact and no current exploitation, and it marks the issue as not automatable.
Affected products and versions
- Microsoft 365 Copilot: the source does not specify versions.
- Microsoft 365 Copilot for iOS: the record gives no version value.
- No version numbers are listed in the record, so none are stated here. Check the vendor advisory for the scope of affected builds.
Exploitation status
The CISA Known Exploited Vulnerabilities catalog does not list this CVE in the record. No confirmed exploitation appears in the sources consulted. The EPSS probability in the record is low.
Remediation and mitigation
- The record contains no fixed versions or patch list. The absence of data here does not mean no fix exists; consult the vendor advisory for current guidance.
- Apply vendor updates to Microsoft 365 Copilot and the iOS client as soon as they are available for your environment.
- Restrict access to Copilot features for untrusted content and limit tool or plugin permissions where administrative controls allow it.
Detection guidance
- Review vendor audit logs and administrative telemetry for unusual Copilot requests, unexpected tool invocations or data changes.
- Monitor for user-reported prompts or documents that caused unexpected behavior, since the vector requires user interaction.
Limitations of the available information
The record does not state affected or fixed versions, the precise attack path, or the exact components involved. The CVSS score comes from the CNA record and has not been independently verified in the sources here. Treat the assessment as provisional until the vendor advisory is reviewed.
Frequently asked questions
What is CVE-2026-41090?
It is a command injection weakness (CWE-77) in Microsoft Copilot that the CNA says allows an unauthorized attacker to perform tampering over a network.
Is this CVE known to be actively exploited?
The record shows it is not listed in the CISA KEV catalog, and no confirmed exploitation appears in the sources consulted.
Which versions are affected?
The record does not specify affected versions, so no version numbers can be stated. Check the vendor advisory for details.
What should administrators do now?
Follow the vendor advisory, apply updates as they become available, and restrict untrusted content and tool permissions where possible.
This analysis was drafted with AI assistance from verified source data and automatically checked against it.