JIT Miscompilation Vulnerability in Mozilla Firefox
CVE-2026-109722

8.1HIGH

Key Information:

Vendor

Mozilla
Status
Firefox
Thunderbird
Vendor
CVE Published:
13 October 2026

What is CVE-2026-109722?

A vulnerability in the Just-In-Time (JIT) compilation component of the JavaScript engine within Mozilla Firefox can lead to potential miscompilation. This issue allows attackers to exploit the vulnerabilities within the execution flow, compromising system integrity. Users are encouraged to update to the latest versions: Firefox 158, Firefox ESR 115.43, or Firefox ESR 153.5, to mitigate potential risks associated with this vulnerability.

Affected Version(s)

Firefox 115.43

Firefox 153.5

Firefox 158

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2074164
https://www.mozilla.org/security/advisories/mfsa2026-106/
https://www.mozilla.org/security/advisories/mfsa2026-107/

CVSS V3.1

Score:
8.1
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

Amy Burnett of OpenAI
.