Information disclosure in Mozilla Firefox
CVE-2026-6770
Other issue in the Storage: IndexedDB component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
Vulnerability class: Information Disclosure
EPSS: 0.049 (91.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L.
Affected products
- Mozilla Firefox — versions 140.10, 150
- Mozilla Thunderbird — versions 140.10, 150
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@mozilla.org (Permissions Required)
- security@mozilla.org (Vendor Advisory)
- security@mozilla.org (Vendor Advisory)
- security@mozilla.org (Vendor Advisory)
- security@mozilla.org (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-6770?
- CVE-2026-6770 is a medium-severity vulnerability in Mozilla Firefox, classified under Information Disclosure. CVSS score: 6.5/10. Published 2026-04-21.
- How severe is CVE-2026-6770?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2026-6770 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.