Description

A maliciously constructed mail header could lead to multiple fields being parsed as one, or potential memory safety violations. This vulnerability was fixed in Thunderbird 156 and Thunderbird 140.16.

Is your site exposed to CVE-2026-92238?

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

Scan my site

References

Other References

https://bugzilla.mozilla.org/show_bug.cgi?id=2060601 https://www.mozilla.org/security/advisories/mfsa2026-94/ https://www.mozilla.org/security/advisories/mfsa2026-95/

Frequently Asked Questions

What is CVE-2026-92238? +

A maliciously constructed mail header could lead to multiple fields being parsed as one, or potential memory safety violations. This vulnerability was fixed in Thunderbird 156 and Thunderbird 140.16.

How do I check if I'm vulnerable to CVE-2026-92238? +

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.