CVE-2020-12426

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2020-07-09 · updated 2026-06-17
Weakness: CWE-787

Description

Mozilla developers and community members reported memory safety bugs present in Firefox 77. 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 < 78.

Affected products

Mozilla Firefox: before 78.0 — fixed in 78.0
openSUSE Leap: 15.1, 15.2

How to fix

Upgrade to a fixed version: Mozilla Firefox 78.0. Check the vendor advisory for mitigations.

References

http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00027.html
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00049.html
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1608068%2C1609951%2C1631187%2C1637682
https://security.gentoo.org/glsa/202007-10
https://www.mozilla.org/security/advisories/mfsa2020-24/
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00027.html
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00049.html
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1608068%2C1609951%2C1631187%2C1637682
https://security.gentoo.org/glsa/202007-10
https://www.mozilla.org/security/advisories/mfsa2020-24/

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