Description

Incorrect boundary conditions in the SVG component. This vulnerability was fixed in Firefox 158.0.1 and Thunderbird 158.0.1.

Is your site exposed to CVE-2026-113399?

Run a free security scan — no signup, results in seconds.

Scan my site

EPSS — Exploit Prediction

0.0049

Probability of exploitation

0.43%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://bugzilla.mozilla.org/show_bug.cgi?id=2079938 https://www.mozilla.org/security/advisories/mfsa2026-111/ https://www.mozilla.org/security/advisories/mfsa2026-114/

Frequently Asked Questions

What is CVE-2026-113399? +

Incorrect boundary conditions in the SVG component. This vulnerability was fixed in Firefox 158.0.1 and Thunderbird 158.0.1.

How do I check if I'm vulnerable to CVE-2026-113399? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.