RCE in Microsoft 365 Copilot
CVE-2026-26133
AI command injection in M365 Copilot allows an unauthorized attacker to disclose information over a network.
Vulnerability class: Command Injection (OS Command Injection)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.006 (45.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 45.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.001
Affected products
- Microsoft 365 Copilot
- Microsoft Edge
- Microsoft Excel
- Microsoft Loop
- Microsoft 365 Copilot For Android — versions 1.0
- Microsoft 365 Copilot For iOS — versions 1.0
- Microsoft Edge For Android — versions 1.0.0
- Microsoft Edge For iOS — versions 1.0.0.0
- Microsoft Excel For Android — versions 16.0.0.0
- Microsoft Excel For iOS — versions 1.0
Weakness classification (CWE)
References
- msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26133 (vendor-advisory, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-26133?
- CVE-2026-26133 is a high-severity vulnerability in Microsoft 365 Copilot, classified under Command Injection. CVSS score: 7.1/10. Published 2026-03-16.
- How severe is CVE-2026-26133?
- High severity. CVSS v3 base score is 7.1 out of 10.