Description
Memory safety bugs present in Firefox 149 and Thunderbird 149. 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 150 and Thunderbird 150.
Affected products
mozilla: firefox; mozilla: thunderbird
References6
- www.mozilla.org/security/advisories/mfsa2026-30/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-33/ Vendor Advisory
- bugzilla.mozilla.org/buglist.cgi?bug_id=1536243%2C1745382%2C185…
- access.redhat.com/security/cve/CVE-2026-6784
- bugzilla.redhat.com/show_bug.cgi?id=2460084
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6784.…
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 30 · as of 13 November 2026
- CWE
- CWE-125CWE-416CWE-787
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