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.
Affected products
mozilla: firefox; mozilla: thunderbird
References6
- www.mozilla.org/security/advisories/mfsa2026-25/ Vendor Advisory
- bugzilla.mozilla.org/buglist.cgi?bug_id=2025475%2C2025477 Broken LinkIssue Tracking
- www.mozilla.org/security/advisories/mfsa2026-28/
- access.redhat.com/security/cve/CVE-2026-5735
- bugzilla.redhat.com/show_bug.cgi?id=2455904
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5735.…
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 19 · as of 12 November 2026
- CWE
- CWE-787CWE-125
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