expat_erl.c in ejabberd before 2.1.7 and 3.x before 3.0.0-alpha-3, and exmpp before 0.9.7, does not properly detect recursion during entity expansion, which allows remote attackers to cause a denial of service (memory and CPU consumption) via a crafted XML document containing a large number of nested entity references, a similar issue to CVE-2003-1564.
https://git.process-one.net/ejabberd/mainline/commit/bd1df027c622e1f96f9eeaac612a6a956c1ff0b6
https://exchange.xforce.ibmcloud.com/vulnerabilities/67769
https://bugzilla.redhat.com/show_bug.cgi?id=700454
http://www.securityfocus.com/bid/48072
http://www.process-one.net/en/ejabberd/release_notes/release_note_ejabberd_2.1.7/
http://www.ejabberd.im/ejabberd-2.1.7
http://www.debian.org/security/2011/dsa-2248
http://secunia.com/advisories/45120
http://secunia.com/advisories/44807
http://secunia.com/advisories/44765
http://lists.fedoraproject.org/pipermail/package-announce/2011-June/062145.html
http://lists.fedoraproject.org/pipermail/package-announce/2011-June/062099.html