s2s/out.c in jabberd2 2.2.16 and earlier does not verify that a request was made for an XMPP Server Dialback response, which allows remote XMPP servers to spoof domains via a (1) Verify Response or (2) Authorization Response.
lists.apple.com/archives/security-announce/2013/Mar/msg00002.html
rhn.redhat.com/errata/RHSA-2012-1538.html
rhn.redhat.com/errata/RHSA-2012-1539.html
secunia.com/advisories/50124
secunia.com/advisories/50859
www.mail-archive.com/jabberd2%40lists.xiaoka.com/msg01903.html
www.openwall.com/lists/oss-security/2012/08/22/5
www.openwall.com/lists/oss-security/2012/08/22/6
www.securityfocus.com/bid/55167
xmpp.org/resources/security-notices/server-dialback/
bugzilla.redhat.com/show_bug.cgi?id=850872
github.com/Jabberd2/jabberd2/commit/aabcffae560d5fd00cd1d2ffce5d760353cf0a4d