CVE-2026-16355: Vulnerability in Mozilla Firefox
JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13.
AI Analysis
Technical Summary
CVE-2026-16355 is a vulnerability caused by just-in-time (JIT) miscompilation within the JavaScript Engine's JIT component in Mozilla Firefox. This flaw could potentially lead to security issues due to incorrect code generation during JIT compilation. Mozilla fixed this vulnerability in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13 as part of a security update addressing multiple high-impact bugs. The vendor advisories confirm the fix and classify the impact as high. There are no confirmed reports of exploitation in the wild for this vulnerability.
Potential Impact
The vulnerability involves JIT miscompilation, which can lead to incorrect execution of JavaScript code and potentially compromise the security of the browser environment. The vendor rates the impact as high, indicating serious security implications if exploited. However, there are no known active exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13. Users and administrators should update to these versions or later to remediate the vulnerability. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-16355: Vulnerability in Mozilla Firefox
Description
JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13.
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16355 is a vulnerability caused by just-in-time (JIT) miscompilation within the JavaScript Engine's JIT component in Mozilla Firefox. This flaw could potentially lead to security issues due to incorrect code generation during JIT compilation. Mozilla fixed this vulnerability in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13 as part of a security update addressing multiple high-impact bugs. The vendor advisories confirm the fix and classify the impact as high. There are no confirmed reports of exploitation in the wild for this vulnerability.
Potential Impact
The vulnerability involves JIT miscompilation, which can lead to incorrect execution of JavaScript code and potentially compromise the security of the browser environment. The vendor rates the impact as high, indicating serious security implications if exploited. However, there are no known active exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13. Users and administrators should update to these versions or later to remediate the vulnerability. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-07-20T21:55:59.129Z
- 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: 6a5f6cb92a4a8d5989262426
Added to database: 07/21/2026, 12:57:29 UTC
Last enriched: 07/21/2026, 13:43:32 UTC
Last updated: 07/21/2026, 21:18:30 UTC
Views: 5
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