CVE-2026-21521: high-severity vulnerability in Microsoft 365 Word Copilot
Word Copilot Information Disclosure Vulnerability
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.4epss 0.6%
Improper neutralization of escape, meta, or control sequences in Copilot allows an unauthorized attacker to disclose information over a network.
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
Affected products
Microsoft · Microsoft 365 Word CopilotRelated CVEs — Microsoft 365 Word Copilot
In the same product, most dangerous first.