CVE-2021-21779: Debian Linux

High severity, CVSS 8.8. EPSS: 2.9% chance of exploitation in the next 30 days.

A use-after-free vulnerability exists in the way Webkit’s GraphicsContext handles certain events in WebKitGTK 2.30.4. A specially crafted web page can lead to a potential information leak and further memory corruption. A victim must be tricked into visiting a malicious web page to trigger this vulnerability.

Affected products

• Debian Debian Linux: version 10.0 only
• Fedoraproject Fedora: version 33 only; version 34 only
• WebKitGTK WebKitGTK: version 2.30.4 only

Published 2021-07-08. Last modified 2026-06-17.