CVE-2026-16357: Vulnerability in Mozilla Firefox
CVE-2026-16357 is a critical vulnerability in Mozilla Firefox's Graphics component caused by incorrect boundary conditions. This flaw allows potential memory safety issues that could lead to high impact on confidentiality, integrity, and availability. The vulnerability was fixed in Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13. No known exploits in the wild have been reported. The CVSS v3.1 base score is 9.8, indicating critical severity.
AI Analysis
Technical Summary
CVE-2026-16357 is a critical memory safety vulnerability in the Graphics component of Mozilla Firefox and Thunderbird, caused by incorrect boundary conditions. This vulnerability affects versions prior to Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13. It can lead to severe impacts on confidentiality, integrity, and availability as indicated by a CVSS score of 9.8. Mozilla has released official fixes in the stated versions. No confirmed exploitation in the wild is currently known. The vulnerability is part of a broader set of memory safety bugs addressed in the same releases.
Potential Impact
The vulnerability allows an attacker to potentially exploit incorrect boundary conditions in the Graphics component, which can lead to memory corruption. This can result in arbitrary code execution, privilege escalation, or denial of service, impacting confidentiality, integrity, and availability of the affected systems. The CVSS score of 9.8 reflects the critical nature of this impact.
Mitigation Recommendations
Official patches fixing this vulnerability are available in Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13. Users and administrators should upgrade to these versions or later to mitigate the risk. There is no indication from the vendor advisories that additional mitigation steps are required beyond applying these updates.
CVE-2026-16357: Vulnerability in Mozilla Firefox
Description
CVE-2026-16357 is a critical vulnerability in Mozilla Firefox's Graphics component caused by incorrect boundary conditions. This flaw allows potential memory safety issues that could lead to high impact on confidentiality, integrity, and availability. The vulnerability was fixed in Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13. No known exploits in the wild have been reported. The CVSS v3.1 base score is 9.8, indicating critical severity.
CVSS v3.1
Score 9.8critical
Affected software
pkg:github/mozilla/firefox-esrRun 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
CVE-2026-16357 is a critical memory safety vulnerability in the Graphics component of Mozilla Firefox and Thunderbird, caused by incorrect boundary conditions. This vulnerability affects versions prior to Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13. It can lead to severe impacts on confidentiality, integrity, and availability as indicated by a CVSS score of 9.8. Mozilla has released official fixes in the stated versions. No confirmed exploitation in the wild is currently known. The vulnerability is part of a broader set of memory safety bugs addressed in the same releases.
Potential Impact
The vulnerability allows an attacker to potentially exploit incorrect boundary conditions in the Graphics component, which can lead to memory corruption. This can result in arbitrary code execution, privilege escalation, or denial of service, impacting confidentiality, integrity, and availability of the affected systems. The CVSS score of 9.8 reflects the critical nature of this impact.
Mitigation Recommendations
Official patches fixing this vulnerability are available in Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13. Users and administrators should upgrade to these versions or later to mitigate the risk. There is no indication from the vendor advisories that additional mitigation steps are required beyond applying these updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-07-20T21:56:03.705Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-68/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-69/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-70/","vendor":"Mozilla"}]
Threat ID: 6a5f6cb92a4a8d5989262432
Added to database: 07/21/2026, 12:57:29 UTC
Last enriched: 07/30/2026, 11:09:27 UTC
Last updated: 09/02/2026, 22:52:09 UTC
Views: 59
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