Critical CVSS 9.3 EPSS 0.0056 2026-05 archive

Executive Summary

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

Overview

9.3
CVSS CRITICAL
Critical
MS Severity
Not Exploited
MS Exploit Status
N/A
MS Exploit Likelihood
Category Tampering
Released May 12 2026
Last Updated May 12 2026
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known
EPSS Score 0.0056 — 0.42116 percentile
NVD CVSS 9.3 CRITICAL — matches MSRC

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N/E:U/RL:O/RC:C
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
None
USER INTERACTION
Required
SCOPE
Changed
CONFIDENTIALITY
High
INTEGRITY
High
AVAILABILITY
None
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 8.1

EPSS Score

0.0056
probability of exploitation in the next 30 days
0.42116 percentile - updated 2026-06-21
View on FIRST.org

Known Exploits

Acknowledgments