Memory safety bugs present in Firefox 139 and Thunderbird 139. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 140.
History

Thu, 03 Jul 2025 16:30:00 +0000

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

Thu, 26 Jun 2025 14:15:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

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

cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H'}


Thu, 26 Jun 2025 00:30:00 +0000

Type Values Removed Values Added
Title firefox: Memory safety bugs fixed in Firefox 140 and Thunderbird 140
References
Metrics threat_severity

None

threat_severity

Important


Wed, 25 Jun 2025 14:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-119
Metrics ssvc

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

ssvc

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


Tue, 24 Jun 2025 19:15:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

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

ssvc

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


Tue, 24 Jun 2025 12:45:00 +0000

Type Values Removed Values Added
Description Memory safety bugs present in Firefox 139 and Thunderbird 139. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 140.
References

cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2025-06-24T12:28:04.830Z

Updated: 2025-06-26T13:27:34.979Z

Reserved: 2025-06-20T14:51:44.671Z

Link: CVE-2025-6436

cve-icon Vulnrichment

Updated: 2025-06-24T17:40:16.016Z

cve-icon NVD

Status : Analyzed

Published: 2025-06-24T13:15:24.677

Modified: 2025-07-03T16:09:47.610

Link: CVE-2025-6436

cve-icon Redhat

Severity : Important

Publid Date: 2025-06-24T12:28:04Z

Links: CVE-2025-6436 - Bugzilla