JavaScript Engine Vulnerability in Firefox by Mozilla
CVE-2026-100814

8.8HIGH

Key Information:

Vendor

Mozilla
Status
Firefox
Thunderbird
Vendor
CVE Published:
29 September 2026

What is CVE-2026-100814?

A flaw in the JavaScript Engine's Just-In-Time (JIT) component has been identified, which results from incorrect boundary conditions. This vulnerability could potentially allow for unexpected behaviors, affecting the stability and security of the Firefox browser. Users are encouraged to update to Firefox ESR 153.4 or Firefox 157 to mitigate any risks associated with this vulnerability.

Affected Version(s)

Firefox 153.4

Firefox 157

Thunderbird 153.4

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2068385
https://www.mozilla.org/security/advisories/mfsa2026-100/
https://www.mozilla.org/security/advisories/mfsa2026-101/

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Mozilla
.