CVE-2021-21111: Debian Linux

Critical severity, CVSS 9.6. EPSS: 1.1% chance of exploitation in the next 30 days.

Insufficient policy enforcement in WebUI in Google Chrome prior to 87.0.4280.141 allowed an attacker who convinced a user to install a malicious extension to potentially perform a sandbox escape via a crafted Chrome Extension.

Affected products

• Debian Debian Linux: version 10.0 only
• Fedoraproject Fedora: version 32 only; version 33 only
• Google Chrome: before 87.0.4280.141 (fixed in 87.0.4280.141)

Published 2021-01-08. Last modified 2026-06-17.