VulnerabilityModified
CVE-2026-2797
Use-after-free in the JavaScript: GC component.
CRITICAL 9.8EPSS 0.32%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.32%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 148 and Thunderbird 148.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.32% probability · 24th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-416
- Affected
- mozilla/firefox · mozilla/thunderbird
- Source
- security@mozilla.org
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=2013561Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2026-13/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-16/Vendor Advisory
- https://access.redhat.com/security/cve/CVE-2026-2797
- https://bugzilla.redhat.com/show_bug.cgi?id=2442330
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2797.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.