CVE-2021-23997

HIGH

Firefox < 88.0 - Use-After-Free via Font Cache Data Type Conversion

Title source: llm
STIX 2.1

Description

Due to unexpected data type conversions, a use-after-free could have occurred when interacting with the font cache. We presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox < 88.

References (2)

Core 2
Core References
Release Notes, Vendor Advisory x_refsource_misc
https://www.mozilla.org/security/advisories/mfsa2021-16/
Issue Tracking, Permissions Required, Vendor Advisory x_refsource_misc
https://bugzilla.mozilla.org/show_bug.cgi?id=1701942

Scores

CVSS v3 8.8
EPSS 0.0082
EPSS Percentile 52.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Details

CWE
CWE-681
Status published
Products (1)
mozilla/firefox < 88.0
Published Jun 24, 2021
Tracked Since Feb 18, 2026