CVE-2026-21521

Published: Jan 22, 2026

Modified: Apr 1, 2026

PUBLISHED

CVSS v3.1

7.4

HIGH

Improper neutralization of escape, meta, or control sequences in Copilot allows an unauthorized attacker to disclose information over a network.

Vendor	Product	Versions
Microsoft	Microsoft 365 Word Copilot	affected `-`

CVSS v3.1 Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/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

None

Availability

None

vendor-advisory

patch

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