A security issue was identified and fixed in ISC INN: The STARTTLS implementation in INN's NNTP server for readers, nnrpd, 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 . The updated packages have been upgraded to inn 2.5.3 which is not vulnerable to this issue.