CVE-2018-12366

Severity: medium (CVSS 6.5 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: 2018-10-18 · updated 2026-06-17
Weakness: CWE-125

Description

An invalid grid size during QCMS (color profile) transformations can result in the out-of-bounds read interpreted as a float value. This could leak private data into the output. This vulnerability affects Thunderbird < 60, Thunderbird < 52.9, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

Affected products

Canonical Ubuntu Linux: 14.04, 16.04, 17.10, 18.04
Debian Linux: 8.0, 9.0
Mozilla Firefox: before 61.0; from 53.0 before 60.1.0 — fixed in 60.1.0, 61.0
Mozilla Firefox ESR: before 52.9 — fixed in 52.9
Mozilla Thunderbird: before 52.9; from 52.9.1 before 60.0 — fixed in 52.9, 60.0
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: 7.5, 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 60.1.0, 61.0; Mozilla Firefox ESR 52.9; Mozilla Thunderbird 52.9, 60.0. Check the vendor advisory for mitigations.

References

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