CVE-2026-8949
high
CVSS v3
7.5
CVSS v4 NEW
—
VIR risk
7.5
Description
Integer overflow in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Predictions
Exploit likelihood
83%
Patch ETA
—
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| debian | sid | fixed | 0 |
| debian | bookworm | fixed | 0 |
| debian | bullseye | fixed | 0 |
| debian | forky | fixed | 0 |
| debian | trixie | fixed | 0 |
| sles | affected | |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| mozilla | firefox | {"endExcluding":"140.11.0"} | 140.11.0 |
| mozilla | thunderbird | {"endExcluding":"140.11"} | 140.11 |
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1355639
- https://www.mozilla.org/security/advisories/mfsa2026-46/
- https://www.mozilla.org/security/advisories/mfsa2026-48/
- https://www.mozilla.org/security/advisories/mfsa2026-50/
- https://www.mozilla.org/security/advisories/mfsa2026-51/
- https://security-tracker.debian.org/tracker/CVE-2026-8949
- https://www.suse.com/security/cve/CVE-2026-8949.html
CWEs
CWE-190
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.