Information disclosure in the Networking: JAR component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact partial

Affected Vendors & Products

Vendors Products
Mozilla
  • Firefox
  • Thunderbird

Configuration 1 [-]

OR cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

No data.

References
Link Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=2061526 cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-100/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-101/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-102/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-103/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-97/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-98/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-99/ cve-icon cve-icon
History

Tue, 13 Oct 2026 18:15:00 +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, 30 Sep 2026 17:45:00 +0000

Type Values Removed Values Added
Description Information disclosure in the Networking: JAR component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. Information disclosure in the Networking: JAR component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
References

Wed, 30 Sep 2026 17:30:00 +0000

Type Values Removed Values Added
Description Information disclosure in the Networking: JAR component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. Information disclosure in the Networking: JAR component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
References

Tue, 29 Sep 2026 18:45:00 +0000

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

Tue, 29 Sep 2026 16:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-200
Metrics cvssV3_1

{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N'}

ssvc

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

Tue, 29 Sep 2026 13:15:00 +0000

Type Values Removed Values Added
Description Information disclosure in the Networking: JAR component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Title Information disclosure in the Networking: JAR component
References
cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2026-09-29T12:35:58.608Z

Updated: 2026-09-30T17:20:03.915Z

Reserved: 2026-09-26T19:15:22.826Z

Link: CVE-2026-100766

cve-icon Vulnrichment

Updated: 2026-09-29T15:09:42.992Z

cve-icon NVD

Status : Analyzed

Published: 2026-09-29T13:17:40.837

Modified: 2026-10-13T18:00:56.640

Link: CVE-2026-100766

cve-icon Redhat

No data.