The ap_proxy_ftp_handler function in modules/proxy/proxy_ftp.c in the mod_proxy_ftp module in the Apache HTTP Server 2.0.63 and 2.2.13 allows remote FTP servers to cause a denial of service (NULL pointer dereference and child process crash) via a malformed reply to an EPSV command.
https://www.redhat.com/archives/fedora-package-announce/2009-December/msg00944.html
https://www.redhat.com/archives/fedora-package-announce/2009-December/msg00645.html
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A8087
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10981
https://bugzilla.redhat.com/show_bug.cgi?id=521619
http://www.vupen.com/english/advisories/2010/0609
http://www.securityfocus.com/archive/1/508075/100/0/threaded
http://www.debian.org/security/2009/dsa-1934
http://www-01.ibm.com/support/docview.wss?uid=swg1PM09161
http://www-01.ibm.com/support/docview.wss?uid=swg1PK96858
http://secunia.com/advisories/37152
http://secunia.com/advisories/36549
http://marc.info/?l=bugtraq&m=133355494609819&w=2
http://marc.info/?l=bugtraq&m=127557640302499&w=2
http://marc.info/?l=bugtraq&m=126998684522511&w=2
http://lists.opensuse.org/opensuse-security-announce/2009-10/msg00006.html