Buffer overflow in HAProxy 1.4 through 1.4.22 and 1.5-dev through 1.5-dev17, when HTTP keep-alive is enabled, using HTTP keywords in TCP inspection rules, and running with rewrite rules that appends to requests, allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via crafted pipelined HTTP requests that prevent request realignment from occurring.
http://www.ubuntu.com/usn/USN-1800-1
http://www.securityfocus.com/bid/58820
http://www.openwall.com/lists/oss-security/2013/04/03/1
http://www.debian.org/security/2013/dsa-2711
http://secunia.com/advisories/52725
http://rhn.redhat.com/errata/RHSA-2013-0868.html
http://rhn.redhat.com/errata/RHSA-2013-0729.html
http://lists.fedoraproject.org/pipermail/package-announce/2013-April/103794.html
http://lists.fedoraproject.org/pipermail/package-announce/2013-April/103770.html
http://lists.fedoraproject.org/pipermail/package-announce/2013-April/103730.html