CVE-2026-5735
Memory safety bugs fixed in Firefox 149.0.2 and Thunderbird 149.0.2
- State
- Published
- Severity
- 8.1 High
- Published
- Apr 7, 2026
- Updated
- Jul 15, 2026
- Reserved
- Apr 7, 2026
Description
Memory safety bugs present in Firefox 149.0.1 and Thunderbird 149.0.1. 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 149.0.2 and Thunderbird 149.0.2.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 8.1 High | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H | CISA-ADP |
| 3.1 | 7.5 High | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H | redhat-SADP |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
FirefoxMozilla |
|
ThunderbirdMozilla |
|
References
- Memory safety bugs fixed in Firefox 149.0.2 and Thunderbird 149.0.2
- https://www.mozilla.org/security/advisories/mfsa2026-25/
- https://www.mozilla.org/security/advisories/mfsa2026-28/
- https://access.redhat.com/security/cve/CVE-2026-5735vdb-entry
- RHBZ#2455904issue-tracking
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5735.json
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