JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
Advisories
Source ID Title
Debian DLA Debian DLA DLA-4750-1 firefox-esr security update
Debian DSA Debian DSA DSA-6451-1 firefox-esr security update
Debian DSA Debian DSA DSA-6461-1 thunderbird security update
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 19 Aug 2026 15:30:00 +0000

Type Values Removed Values Added
First Time appeared Mozilla thunderbird
CPEs cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
Vendors & Products Mozilla thunderbird

Wed, 19 Aug 2026 13:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-843
Metrics cvssV3_1

{'score': 3.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:N/A:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N'}


Wed, 19 Aug 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-733
References
Metrics threat_severity

None

cvssV3_1

{'score': 3.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:N/A:N'}

threat_severity

Low


Tue, 18 Aug 2026 22:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-119
CWE-190

Tue, 18 Aug 2026 19:00:00 +0000

Type Values Removed Values Added
Description JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1. JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
References

Tue, 18 Aug 2026 14:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-119
CWE-190

Tue, 18 Aug 2026 14:00:00 +0000

Type Values Removed Values Added
First Time appeared Mozilla
Mozilla firefox
Vendors & Products Mozilla
Mozilla firefox

Tue, 18 Aug 2026 12:45:00 +0000

Type Values Removed Values Added
Description JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1.
Title JIT miscompilation in the JavaScript Engine: JIT component
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published:

Updated: 2026-08-19T13:04:07.566Z

Reserved: 2026-08-17T11:58:57.547Z

Link: CVE-2026-74976

cve-icon Vulnrichment

Updated: 2026-08-19T13:03:15.343Z

cve-icon NVD

Status : Analyzed

Published: 2026-08-18T13:17:35.580

Modified: 2026-08-19T15:24:04.953

Link: CVE-2026-74976

cve-icon Redhat

Severity : Low

Publid Date: 2026-08-18T12:23:34Z

Links: CVE-2026-74976 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-08-21T18:15:04Z

Weaknesses