Buffer overflow in nnrpd program in INN up to version 1.6 allows remote users to execute arbitrary commands.

Command execution via shell metachars in INN daemon (innd) 1.5 using "newgroup" and "rmgroup" control messages, and others.

Buffer overflow in INN 2.2.1 and earlier allows remote attackers to cause a denial of service via a maliciously formatted article.

The STARTTLS implementation in nnrpd in INN before 2.5.3 does not properly restrict I/O buffering, which allows man-in-the-middle attackers to insert commands into encrypted sessions by sending a cleartext command that is processed after TLS is in place, related to a "plaintext command injection" attack, a similar issue to CVE-2011-0411.