CVE-2020-12389

CriticalCVSS 10.0/10Last modified Jun 17, 2026

Description

The Firefox content processes did not sufficiently lockdown access control which could result in a sandbox escape. *Note: this issue only affects Firefox on Windows operating systems.*. This vulnerability affects Firefox ESR < 68.8 and Firefox < 76.

Metrics

CVSS 3.1 10.0/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Weakness enumeration

CWE-20

Affected software

Vendor	Product	Versions
Mozilla	Firefox ESR	>= unspecified, < 68.8
Mozilla	Firefox	>= unspecified, < 76

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1554110Permissions Required
https://www.mozilla.org/security/advisories/mfsa2020-16/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-17/Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1554110Permissions Required
https://www.mozilla.org/security/advisories/mfsa2020-16/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-17/Vendor Advisory

Timeline

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

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