CVE-2026-4725 describes a critical sandbox escape vulnerability stemming from a use-after-free flaw within the Graphics: Canvas2D component, affecting Mozilla Firefox and Thunderbird versions prior to 149. This vulnerability carries a CVSS score of 10.0 CRITICAL, indicating a network-based attack with low complexity, requiring no user interaction or privileges. Successful exploitation could lead to remote code execution and complete system compromise due to the sandbox escape. While there is no evidence of active exploitation, public exploit code, or inclusion in the CISA KEV catalog, community discussions acknowledge the severe potential impact of this flaw.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 149.0CPE matchmatch criteria | cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.
The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.