CVE-2026-21521 (GCVE-0-2026-21521)

Vulnerability from cvelistv5 – Published: 2026-01-22 22:47 – Updated: 2026-01-30 03:40 Exclusively Hosted Service
VLAI?
Title
Word Copilot Information Disclosure Vulnerability
Summary
Improper neutralization of escape, meta, or control sequences in Copilot allows an unauthorized attacker to disclose information over a network.
Severity ?
7.4 (High)
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
CWE
  • CWE-150 - Improper Neutralization of Escape, Meta, or Control Sequences
Assigner
References
Impacted products
Vendor Product Version
Microsoft Microsoft 365 Word Copilot Affected: -
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.