Squid 2.5.STABLE8 and earlier allows remote attackers to cause a denial of service (crash) via certain DNS responses regarding (1) Fully Qualified Domain Names (FQDN) in fqdncache.c or (2) IP addresses in ipcache.c, which trigger an assertion failure.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11264
https://exchange.xforce.ibmcloud.com/vulnerabilities/19332
http://www.squid-cache.org/Versions/v2/2.5/bugs/squid-2.5.STABLE8-dns_assert.patch
http://www.squid-cache.org/Versions/v2/2.5/bugs/#squid-2.5.STABLE8-dns_assert
http://www.securityfocus.com/bid/12551
http://www.redhat.com/support/errata/RHSA-2005-201.html
http://www.redhat.com/support/errata/RHSA-2005-173.html
http://www.mandriva.com/security/advisories?name=MDKSA-2005:047
http://www.gentoo.org/security/en/glsa/glsa-200502-25.xml
http://www.debian.org/security/2005/dsa-688
http://secunia.com/advisories/14271
http://marc.info/?l=bugtraq&m=110901183320453&w=2
http://fedoranews.org/updates/FEDORA--.shtml
http://distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000931