Hiyas,
there is a security update for proftpd that fixes a remote code
execution vulnerability that is currently being exploited still in
testing:
https://admin.fedoraproject.org/updates/proftpd-1.3.3c-1.el5
https://admin.fedoraproject.org/updates/proftpd-1.3.3c-1.el4
Afaik, this should be pushed to stable asap.
Regards
Till