JIT Miscompilation in JavaScript Engine for Mozilla Firefox
CVE-2026-16410

9.8CRITICAL

Key Information:

Vendor

Mozilla
Status
Firefox
Thunderbird
Vendor
CVE Published:
21 July 2026

What is CVE-2026-16410?

The JIT miscompilation vulnerability in the JavaScript engine of Mozilla Firefox could potentially lead to unexpected behavior during code execution. This flaw, which was addressed in Firefox version 153, highlights the importance of keeping software updated to mitigate risks associated with execution errors that arise from Just-In-Time compilation processes.

Affected Version(s)

Firefox 153

Thunderbird 153

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2053680
https://www.mozilla.org/security/advisories/mfsa2026-68/
https://www.mozilla.org/security/advisories/mfsa2026-71/

CVSS V3.1

Score:
9.8
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Amy Burnett of OpenAI
.