CVE-2026-6759 — Use After Free in Mozilla Firefox

CWE-416 — Use After FreeCWE-825 — Expired Pointer Dereference9 documents6 sources
Severity
7.5HIGHNVD
EPSS
0.1%
top 80.98%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
3
Mozilla FirefoxMozilla Firefox ESRMozilla Thunderbird
Timeline
PublishedApr 21

Description

Use-after-free in the Widget: Cocoa component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitability: 3.9 | Impact: 3.6

Affected Packages3 packages

▶Mozillamozilla/firefox< Firefox 150
▶Mozillamozilla/firefox_esr< Firefox ESR 140.10
▶Mozillamozilla/thunderbird< Thunderbird 150+1

🔴Vulnerability Details

1
GHSA
GHSA-w4vh-g4vq-3rf9: Use-after-free in the Widget: Cocoa component↗2026-04-21
▶

📋Vendor Advisories

6
Red Hat
firefox: Use-after-free in the Widget: Cocoa component↗2026-04-21
▶
Mozilla
Mozilla Foundation Security Advisory 2026-32: CVE-2026-6759↗
▶
Mozilla
Mozilla Foundation Security Advisory 2026-30: CVE-2026-6759↗
▶
Mozilla
Mozilla Foundation Security Advisory 2026-33: CVE-2026-6759↗
▶
Mozilla
Mozilla Foundation Security Advisory 2026-34: CVE-2026-6759↗
▶

💬Community

1
Bugzilla
CVE-2026-6759 firefox: Use-after-free in the Widget: Cocoa component↗2026-04-21
▶
CVE-2026-6759 — Use After Free in Mozilla Firefox | cvebase