VULNERABILITY INTELLIGENCE

CVE-2021-29966

CVSS score8.8 HIGH

EPSS probability1.02%

CISA KEVNot currently listed

Published2021-06-24

Last modified2026-06-17

CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Description

Mozilla developers reported memory safety bugs present in Firefox 88. 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 < 89.

Weakness classification

CWE-787: Out-of-bounds Write

Primary references

security@mozilla.org — Broken Link, Issue Tracking
security@mozilla.org — Third Party Advisory
security@mozilla.org — Release Notes, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108 — Broken Link, Issue Tracking
af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108 — Release Notes, Vendor Advisory