CVE-2026-12326: Mozilla Firefox

Affected products, as the CNA wrote them
Vendor	Product	Versions
Mozilla	Firefox	unaffected 152 to *, inclusive rpm
Mozilla	Thunderbird	unaffected 152 to *, inclusive rpm

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
8.1	High	3.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H	ADP (CISA-ADP)Used for this record
7.5	High	3.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H	ADP (redhat-SADP)

CISA KEV Not listed.
EPSS 0.0036, the 30th percentile, on 10 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of the CVE Program, published 16 Jun 2026. New records show when each source confirmed them.

Sources

CVE List: CVE-2026-12326
NVD: CVE-2026-12326

References from the CNA

bugzilla.mozilla.org/buglist.cgi?bug_id=1767455%2C2004308%2C2024445%2C2028182%2C2029765%2C2029883%2C2030110%2C2030149%2C2030366%2C2030374%2C2030564%2C2031120%2C2033411%2C2038695%2C2042465%2C2042781%2C2042907
bugzilla.mozilla.org/buglist.cgi?bug_id=2021955%2C2025960%2C2029066%2C2029403%2C2029435%2C2029803%2C2030570%2C2030573%2C2032264%2C2033234%2C2034816%2C2035907%2C2035963%2C2036895%2C2036898%2C2036907%2C2036909%2C2036928%2C2036931%2C2036932%2C2036934%2C2039238%2C2039463
bugzilla.mozilla.org/buglist.cgi?bug_id=2039050%2C2042718%2C2042760%2C2044831%2C2045307%2C2045398%2C2045516%2C2045572%2C2041741%2C2044433
www.mozilla.org/security/advisories/mfsa2026-57/
www.mozilla.org/security/advisories/mfsa2026-60/

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.