CVE-2021-23997

Published: Jun 24, 2021Modified: Jun 17, 2026

8.8

Vector

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

Exploitability: 2.8 / Impact: 5.9

Source: NVD

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.

Affected (1)

Products: Mozilla: Firefox

Mozilla

1 product

Firefox

Configuration A

1 vulnerable

Vulnerable Software	Affected Versions
Mozilla Firefox	Before 88.0

Related CWEs

CWE-681

Incorrect Conversion between Numeric Types

When converting from one data type to another, such as long to integer, data can be omitted or translated in a way that produces unexpected values. If the resulting values are used in a sensitive context, then dangerous behaviors may occur.

References (4)

https://bugzilla.mozilla.org/show_bug.cgi?id=1701942

Source: security@mozilla.org

Issue TrackingPermissions RequiredVendor Advisory

https://www.mozilla.org/security/advisories/mfsa2021-16/

Source: security@mozilla.org

Release NotesVendor Advisory

https://bugzilla.mozilla.org/show_bug.cgi?id=1701942

Source: af854a3a-2127-422b-91ae-364da2661108

Issue TrackingPermissions RequiredVendor Advisory

https://www.mozilla.org/security/advisories/mfsa2021-16/

Source: af854a3a-2127-422b-91ae-364da2661108

Release NotesVendor Advisory

Timeline

No history available yet.