TI-2021-03004 Aliases CVE-2021-4128 GHSA-qx74-qh3q-h8rj

Use after free in Mozilla Firefox

MEDIUM 62CWE-416Published 2022-12-22 · Updated 2025-04-16

Key facts

Attack vector: Network
Privileges required: None
User interaction: Required
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.

Summary

When transitioning in and out of fullscreen mode, a graphics object was not correctly protected; resulting in memory corruption and a potentially exploitable crash.<br>*This bug only affects Firefox on MacOS. Other operating systems are unaffected.*. This vulnerability affects Firefox < 95.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00575 47th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix Fixed Firefox (Mozilla): 95

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Mozilla	Firefox	before 95	95	Patch available	CNA

Firefox VendorMozilla Affected before 95 Fixed in 95 Patch available CNA

CPE configurations NVD · 2

CPE	Versions	Role	Vendor
cpe:2.3:a:mozilla:firefox::::::::	before 95.0	Vulnerable	Mozilla
cpe:2.3:o:apple:macos:-:::::::*	not specified by NVD	Running on	Apple

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* Versions before 95.0 Vulnerable ·Mozilla
cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Apple

Remediation

Fix · CNA Firefox (Mozilla) Fixed in 95

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2022-12-22
Mozilla Firefox 95
2 records Highest priority Priority MEDIUM 2 MEDIUM
Other records, highest priority first
- TI-2021-03005 Out-of-bounds write in Mozilla FirefoxPriority MEDIUM 51
Show all 2 records →

Timeline

2026-10-02 Threatist record created from CVE-2021-4128
2026-10-03 Alias added: GHSA-qx74-qh3q-h8rj

References

Exploit 1

https://bugzilla.mozilla.org/show_bug.cgi?id=1735852

Advisory 1

https://www.mozilla.org/security/advisories/mfsa2021-52/

TI-2024-08981 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.8
TI-2022-09832 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.6
TI-2019-08769 Improper input validation in Mozilla Firefox ESR KEVCVSS 3.1CRITICAL 10.0
TI-2010-03577 Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before… KEVCVSS 3.1CRITICAL 9.8
TI-2023-04799 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
TI-2023-04477 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8

See all 3444 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences