proftpd -- remote code execution vulnerability

Tippingpoint reports:

This vulnerability allows remote attackers to execute arbitrary
code on vulnerable installations of ProFTPD. Authentication is not
required to exploit this vulnerability.
The flaw exists within the proftpd server component which
listens by default on TCP port 21. When reading user input if a
TELNET_IAC escape sequence is encountered the process
miscalculates a buffer length counter value allowing a user
controlled copy of data to a stack buffer. A remote attacker can
exploit this vulnerability to execute arbitrary code under the
context of the proftpd process.