RCE in Microsoft Copilot

CVE-2026-55145

Improper neutralization of special elements used in a command ('command injection') in Outlook Copilot allows an authorized attacker to perform tampering over a network.

Vulnerability class: Command Injection (OS Command Injection)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:L/A:N.

EPSS exploit prediction

EPSS: 0.005 (43.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-55145: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-55145?
CVE-2026-55145 is a medium-severity vulnerability in Microsoft Copilot, classified under Command Injection. CVSS score: 6.3/10. Published 2026-07-14.
How severe is CVE-2026-55145?
Medium severity. CVSS v3 base score is 6.3 out of 10.