critical9.8
CVE-2026-4729
Memory safety bugs present in Firefox 148 and Thunderbird 148.
Impact
Memory safety bugs present in Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 149 and Thunderbird 149.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Mozilla | Firefox | before 149.0 |
| Mozilla | Thunderbird | before 149.0 |
Weakness classification
References
- NVD record
- CVE.org record
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=1944033%2C1997282%2C2009213%2C2011412%2C2021925%2C2022034
- https://www.mozilla.org/security/advisories/mfsa2026-20/
- https://www.mozilla.org/security/advisories/mfsa2026-23/
- https://access.redhat.com/security/cve/CVE-2026-4729
- https://bugzilla.redhat.com/show_bug.cgi?id=2450745
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4729.json