The parse_request function in request.c in c-icap 0.2.x allows remote attackers to cause a denial of service (crash) via a URI without a " " or "?" character in an ICAP request, as demonstrated by use of the OPTIONS method.
http://www.mandriva.com/security/advisories?name=MDVSA-2015:001
http://sourceforge.net/p/c-icap/code/1018/
http://security.gentoo.org/glsa/glsa-201409-07.xml