CVE-2020-12398

If Thunderbird is configured to use STARTTLS for an IMAP server, and the server sends a PREAUTH response, then Thunderbird will continue with an unencrypted connection, causing email data to be sent without protection. This vulnerability affects Thunderbird < 68.9.0.

• CWE-319

• https://bugzilla.mozilla.org/show_bug.cgi?id=1613623Issue Tracking, Permissions Required, Vendor Advisory
• https://usn.ubuntu.com/4421-1/Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-22/Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1613623Issue Tracking, Permissions Required, Vendor Advisory
• https://usn.ubuntu.com/4421-1/Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-22/Vendor Advisory

Published

Jul 9, 2020

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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