CVE-2020-12396

CriticalCVSS 9.8/10Last modified Jun 17, 2026

Description

Mozilla developers and community members reported memory safety bugs present in Firefox 75. 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 affects Firefox < 76.

Metrics

CVSS 3.1 9.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-787

Affected software

Vendor	Product	Versions
Mozilla	Firefox	>= unspecified, < 76

References

https://bugzilla.mozilla.org/buglist.cgi?bug_id=1339601%2C1611938%2C1620488%2C1622291%2C1627644Broken Link, Issue Tracking
https://security.gentoo.org/glsa/202005-04Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2020-16/Vendor Advisory
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1339601%2C1611938%2C1620488%2C1622291%2C1627644Broken Link, Issue Tracking
https://security.gentoo.org/glsa/202005-04Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2020-16/Vendor Advisory

Timeline

Published: May 26, 2020
Last modified: Jun 17, 2026
NVD status: Modified

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