Home/CVE/Improper neutralization of escape, meta, or control sequences in Copilot allows an unauthorized attacker to disclose inf
CVE

CVE-2026-21521

Improper neutralization of escape, meta, or control sequences in Copilot allows an unauthorized attacker to disclose inf

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

HIGH · CVSS 7.4 EPSS 0.00124
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-150Improper Neutralization of Escape, Meta, or Control Sequences
▤

Affected Products & Versions

1
microsoft 365 word copilotall versions
▣

Scoring & Timeline

7.4
HIGH · CVSS v3.1 · secure@microsoft.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD22 Jan 2026 · 11:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
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Vendor Advisories

1
msrcCVE-2026-21521Information Disclosure
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