What is CVE-2026-12320?

CVE-2026-12320 is a medium-severity vulnerability in Mozilla Firefox, classified under Information Disclosure. CVSS score: 4.3/10. Published 2026-06-16.

How severe is CVE-2026-12320?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Information disclosure in Mozilla Firefox

CVE-2026-12320

Information disclosure in the Password Manager component. This vulnerability was fixed in Firefox 152 and Thunderbird 152.

Vulnerability class: Information Disclosure

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N.

Affected products

Mozilla Firefox — versions 152
Mozilla Thunderbird — versions 152

Weakness classification (CWE)

CWE-200 — Information Disclosure

References

security@mozilla.org
security@mozilla.org
security@mozilla.org

Frequently asked questions

What is CVE-2026-12320?: CVE-2026-12320 is a medium-severity vulnerability in Mozilla Firefox, classified under Information Disclosure. CVSS score: 4.3/10. Published 2026-06-16.
How severe is CVE-2026-12320?: Medium severity. CVSS v3 base score is 4.3 out of 10.