CVE-2026-16361: Vulnerability in Mozilla Firefox
Memory safety bugs present in Thunderbird ESR 140.12. 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 was fixed in Firefox ESR 115.38, Firefox ESR 140.13, and Thunderbird 140.13.
AI Analysis
Technical Summary
This vulnerability involves memory safety bugs in Mozilla Firefox ESR 115.37 and 140.12. Some of these bugs showed evidence of memory corruption, which could have allowed attackers to execute arbitrary code with sufficient effort. The vulnerability is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). Mozilla addressed these issues by releasing fixed versions Firefox ESR 115.38 and 140.13. The CVSS v3.1 base score is 9.8, indicating critical severity with network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation of this vulnerability could allow remote attackers to execute arbitrary code on affected systems without any privileges or user interaction. This poses a critical risk to confidentiality, integrity, and availability of the affected systems running vulnerable Firefox ESR versions.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox ESR versions 115.38 and 140.13. Users and administrators should update to these or later versions to remediate the issue. There are no indications of active exploitation in the wild. Patch status is confirmed by Mozilla advisories mfsa2026-69 and mfsa2026-70.
CVE-2026-16361: Vulnerability in Mozilla Firefox
Description
Memory safety bugs present in Thunderbird ESR 140.12. 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 was fixed in Firefox ESR 115.38, Firefox ESR 140.13, and Thunderbird 140.13.
CVSS v3.1
Score 9.8critical
Affected software
pkg:github/mozilla/firefoxRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves memory safety bugs in Mozilla Firefox ESR 115.37 and 140.12. Some of these bugs showed evidence of memory corruption, which could have allowed attackers to execute arbitrary code with sufficient effort. The vulnerability is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). Mozilla addressed these issues by releasing fixed versions Firefox ESR 115.38 and 140.13. The CVSS v3.1 base score is 9.8, indicating critical severity with network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation of this vulnerability could allow remote attackers to execute arbitrary code on affected systems without any privileges or user interaction. This poses a critical risk to confidentiality, integrity, and availability of the affected systems running vulnerable Firefox ESR versions.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox ESR versions 115.38 and 140.13. Users and administrators should update to these or later versions to remediate the issue. There are no indications of active exploitation in the wild. Patch status is confirmed by Mozilla advisories mfsa2026-69 and mfsa2026-70.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-07-20T21:56:10.203Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-69/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-70/","vendor":"Mozilla"}]
Threat ID: 6a5f6cbb2a4a8d5989262503
Added to database: 07/21/2026, 12:57:31 UTC
Last enriched: 07/30/2026, 03:49:12 UTC
Last updated: 08/30/2026, 10:52:07 UTC
Views: 80
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