CVE-2026-4723

Impact

Use-after-free in the JavaScript Engine component. This vulnerability was fixed in Firefox 149 and Thunderbird 149.

Affected products

Weakness classification

References

• NVD record
• CVE.org record
• https://bugzilla.mozilla.org/show_bug.cgi?id=2013573
• https://www.mozilla.org/security/advisories/mfsa2026-20/
• https://www.mozilla.org/security/advisories/mfsa2026-23/