CVE-2026-92239

HIGH 8.1

Buffer overrun in IMAP

CVSS Score

8.1

EPSS Score

0.2%

EPSS Percentile

8th

A maliciously constructed IMAP line could cause an out-of-bounds buffer read. This vulnerability was fixed in Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

Vendor	mozilla
Product	thunderbird
Ecosystems	Browser JavaScript
Industries	Technology
Published	Sep 15, 2026
Last Updated	Sep 22, 2026

Stay Ahead of the Next One

Get instant alerts for mozilla thunderbird

Be the first to know when new high vulnerabilities affecting mozilla thunderbird are published — delivered to Slack, Telegram or Discord.

Get Free Alerts → Free · No credit card · 60 sec setup

Affected Versions

Mozilla / Thunderbird

All versions affected

References

NVD ↗ CVE.org ↗ EPSS Data ↗

bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2060488 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-94/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-95/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-96/

Credits

Ramesh Adhikari, Dr. Faruk Kazi (CoE-CNDS Lab, VJTI, Mumbai, India)