The SMTP client in Mozilla Thunderbird 1.0.5 BETA, 1.0.7, and possibly other versions, does not notify users when it cannot establish a secure channel with the server, which allows remote attackers to obtain authentication information without detection via a man-in-the-middle (MITM) attack that bypasses TLS authentication or downgrades CRAM-MD5 authentication to plain authentication.
NVD-CWE-Other