CVE-2026-6758

Use-after-free in the JavaScript: WebAssembly component

State: Published
Severity: 7.5 High
Published: Apr 21, 2026
Updated: May 26, 2026
Reserved: Apr 21, 2026

Description

Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Scores

CVSS	Score	Vector	Source
3.1	7.5 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	CISA-ADP

Weaknesses

CWE-416 Use After Free

Affected Products

Product	Versions
FirefoxMozilla	150 and laterNot affected
ThunderbirdMozilla	150 and laterNot affected

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2013619
https://www.mozilla.org/security/advisories/mfsa2026-30/
https://www.mozilla.org/security/advisories/mfsa2026-33/

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