A stack overflow bug has been identified in ProFTPd. This bug allows users to gain remote access (usually root) to an attacker. This bug requires immediate attention and potentially a restore to the last backup image of your server.
Information on the bug can be found here:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2010-4221
We have been handling the issue per https://rimuhosting.com/admin/maintenance.jsp?server_maint_oid=203118951
We use nmap -sV -p 21 ipaddress to identify is the server reports it is running proftpd.
We needed to disable it on some servers while the exploit is unresolved by various vendors/distro makers.
Trying to get a script that works across a variety of different server setups proved ‘interesting’. Here are some details on that for non-RimuHosting ProFTP users that may want to disable that service…
{ set -x; # if you are unlucky you may see some 'suspicious' looking processes spawned by proftpd at this point. Indicating you may have been exploited. ps auxf | grep --after-context 4 "pro[f]tp" | grep -v grep cd /etc/init.d/ chkconfig --del proftp*; update-rc.d -f proftp* remove ; service proftp* stop; /etc/init.d/proftpd stop; [ -e /etc/xinetd.d/ftp_psa ] && mv /etc/xinetd.d/ftp_psa /root/ && echo disabling psa_ftp && /etc/init.d/xinetd restart grep ftp /etc/inetd.conf && sed --in-place 's/^ftp/\#exploitable ftp/' /etc/inetd.conf && grep ftp /etc/inetd.conf && { /etc/init.d/inetd restart ; /etc/init.d/openbsd-inetd restart ; /etc/init.d/xinetd restart; /etc/init.d/inetutils-inetd restart; } set +x } 2>&1 | tee -a proftpdremoveresults
This will try to disable ProFTPd from starting up in various ways (/etc/init.d; service; inetd). And will create a log of what happened.