Auth bypass in Mozilla Firefox

CVE-2018-18505

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.

Vulnerability class: Broken Authentication

Published · last modified .

CVSS v3 metric

CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.044 (91.0th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 91st percentile — 91.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2018-18505: held from 0.045 to 0.044.

EPSS over last 30 days · oldest: 0.045 · newest: 0.044 · change: -0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2018-18505?
CVE-2018-18505 is a critical-severity vulnerability in Mozilla Firefox, classified under Improper Authentication. CVSS score: 10.0/10. Published 2019-02-05.
How severe is CVE-2018-18505?
Critical severity. CVSS v3 base score is 10.0 out of 10.