Description
Improper neutralization of special elements used in a command ('command injection') in M365 Copilot allows an unauthorized attacker to disclose information over a network.
Affected products
microsoft: 365 copilot chat
References1
- msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26129 Vendor Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 1% percentile: 67 · as of 13 November 2026
- CWE
- CWE-138
Could this be exploited in your environment?
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