High7.5Red Hat & Ubuntu Linux
Use-after-free in the JavaScript Engine: JIT component
CVE-2026-2766 Published Feb 24, 2026
CVE-2026-2766
Affected products & platforms
Red Hat & Ubuntu LinuxUnclassified
Summary
Use-after-free in the JavaScript Engine: JIT component. Red Hat rates this important (CVSS 7.5). Affected package(s): thunderbird, firefox. Resolved in Red Hat advisory RHSA-2026:3984 — update the affected packages (`sudo dnf update`).
Affected versions
- thunderbird-0:140.8.0-1.el9_0
- thunderbird-0:140.8.0-1.el8_6
- thunderbird-0:140.8.0-1.el9_6
- thunderbird-0:140.8.0-1.el8_8
- thunderbird-0:140.8.0-1.el9_7
- thunderbird-0:140.8.0-1.el8_2
- thunderbird-0:140.8.0-1.el9_2
- thunderbird-0:140.8.0-1.el9_4
- thunderbird-0:140.8.0-1.el8_10
- firefox-0:140.8.0-2.el8_2
- firefox-0:140.8.0-2.el9_0
- firefox-0:140.8.0-2.el8_4
Official advisory · high-confidence parse· fetched 6 hours ago·verify at source
Fixed versions
- RHSA-2026:3984
Official advisory · high-confidence parse· fetched 6 hours ago·verify at source
Mitigation checklist
Recommended fix / mitigation
- Update the affected package(s) to the fixed version shipped in RHSA-2026:3984 (`sudo dnf update` / `yum update`).
Official advisory · high-confidence parse· fetched 6 hours ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.