libetpan is a portable, efficient framework for different kinds of mail access: IMAP, SMTP, POP and NNTP.
Affected versions of this package are vulnerable to Man-in-the-Middle (MitM). LibEtPan has a STARTTLS buffering issue that affects the IMAP, SMTP, and POP3 protocol. When a server sends a "begin TLS" response, the client reads additional data (e.g., from a meddler-in-the-middle attacker) and evaluates it in a TLS context, aka "response injection."
A fix was pushed into the
master branch but not yet published.