CVE-2018-18505

Severity: critical (CVSS 10.0 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 4.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-02-05 · updated 2026-06-17
Weakness: CWE-287

Description

An earlier fix for an Inter-process Communication (IPC) vulnerability, CVE-2011-3079, added authentication to communication between IPC endpoints and server parents during IPC process creation. This authentication is insufficient for channels created after the IPC process is started, leading to the authentication not being correctly applied to later channels. This could allow for a sandbox escape through IPC channels due to lack of message validation in the listener process. This vulnerability affects Thunderbird < 60.5, Firefox ESR < 60.5, and Firefox < 65.

Affected products

Canonical Ubuntu Linux: 14.04, 16.04, 18.04, 18.10
Debian Linux: 8.0, 9.0
Mozilla Firefox: before 60.5.0; before 65.0 — fixed in 60.5.0, 65.0
Mozilla Thunderbird: before 60.5.0 — fixed in 60.5.0
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 60.5.0, 65.0; Mozilla Thunderbird 60.5.0. Check the vendor advisory for mitigations.

References

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