CVE-2018-12405

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-02-28 · updated 2026-06-17
Weakness: CWE-119

Description

Mozilla developers and community members reported memory safety bugs present in Firefox 63 and Firefox ESR 60.3. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Thunderbird < 60.4, Firefox ESR < 60.4, and Firefox < 64.

Affected products

Canonical Ubuntu Linux: 14.04, 16.04, 18.04, 18.10
Debian Linux: 8.0, 9.0
Mozilla Firefox: before 60.4.0; before 64.0 — fixed in 60.4.0, 64.0
Mozilla Thunderbird: before 60.4.0 — fixed in 60.4.0
RedHat Enterprise Linux Desktop: 6.0, 7.0
RedHat Enterprise Linux Server: 6.0, 7.0
RedHat Enterprise Linux Server Aus: 7.6
RedHat Enterprise Linux Server Eus: 7.6
RedHat Enterprise Linux Server Tus: 7.6
RedHat Enterprise Linux Workstation: 6.0, 7.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 60.4.0, 64.0; Mozilla Thunderbird 60.4.0. Check the vendor advisory for mitigations.

References

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