CVE-2026-4689
10.0 · CRITICALOverview
CVE-2026-4689 is a critical-severity vulnerability affecting mozilla firefox. It was published on March 24, 2026 and has a CVSS 3.1 base score of 10.0 (CRITICAL).
This vulnerability has a CVSS 3.1 base score of 10.0, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
Remediation
Check the references section for vendor advisories and patches from mozilla. Update firefox to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| mozilla | firefox | >= 0, < 115.34.0 | Affected |
| mozilla | thunderbird | >= 0, < 140.9.0 | Affected |
References
Frequently Asked Questions
What is CVE-2026-4689?
CVE-2026-4689 is a critical-severity vulnerability affecting mozilla firefox. It was published on March 24, 2026 and has a CVSS 3.1 base score of 10.0 (CRITICAL).
How severe is CVE-2026-4689?
This vulnerability has a CVSS 3.1 base score of 10.0, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-4689?
Check the references section for vendor advisories and patches from mozilla. Update firefox to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-4689?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-4689 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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