The mod_dav_svn Apache HTTPD server module in Apache Subversion 1.x before 1.7.19 and 1.8.x before 1.8.11 allows remote attackers to cause a denial of service (NULL pointer dereference and server crash) via a REPORT request for a resource that does not exist.
https://support.apple.com/HT204427
http://www.ubuntu.com/usn/USN-2721-1
http://www.securityfocus.com/bid/71726
http://www.debian.org/security/2014/dsa-3107
http://subversion.apache.org/security/CVE-2014-3580-advisory.txt
http://secunia.com/advisories/61131
http://rhn.redhat.com/errata/RHSA-2015-0166.html
http://rhn.redhat.com/errata/RHSA-2015-0165.html
http://lists.apple.com/archives/security-announce/2015/Mar/msg00003.html