Description
Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Published: 2026-05-19
Score: 9.8 Critical
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

No vendor fix or workaround currently provided.

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Tracking

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Advisories
Source ID Title
Debian DLA Debian DLA DLA-4592-1 firefox-esr security update
Debian DLA Debian DLA DLA-4594-1 thunderbird security update
Debian DSA Debian DSA DSA-6283-1 firefox-esr security update
Debian DSA Debian DSA DSA-6288-1 thunderbird security update
History

Fri, 22 May 2026 00:15:00 +0000


Wed, 20 May 2026 14:45:00 +0000

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

Tue, 19 May 2026 20:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-680

Tue, 19 May 2026 17:45:00 +0000

Type Values Removed Values Added
Description Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11. Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
References

Tue, 19 May 2026 17:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-190
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Tue, 19 May 2026 16:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-680

Tue, 19 May 2026 15:15:00 +0000

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

Tue, 19 May 2026 13:45:00 +0000

Type Values Removed Values Added
Description Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11.
Title Integer overflow in the Networking: JAR component
References

Subscriptions

Mozilla Firefox Thunderbird
cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published:

Updated: 2026-05-19T17:10:49.476Z

Reserved: 2026-05-19T12:29:50.365Z

Link: CVE-2026-8956

cve-icon Vulnrichment

Updated: 2026-05-19T16:39:14.659Z

cve-icon NVD

Status : Analyzed

Published: 2026-05-19T14:16:51.943

Modified: 2026-06-17T11:04:40.220

Link: CVE-2026-8956

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-05-19T12:29:51Z

Links: CVE-2026-8956 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-05-19T21:30:14Z

Weaknesses