Squid 2.4 STABLE3 and earlier allows remote attackers to cause a denial of service (core dump) and possibly execute arbitrary code with an ftp:// URL with a larger number of special characters, which exceed the buffer when Squid URL-escapes the characters.
http://www.securityfocus.com/bid/4148
http://www.redhat.com/support/errata/RHSA-2002-029.html
http://www.novell.com/linux/security/advisories/2002_008_squid_txt.html
http://www.linux-mandrake.com/en/security/2002/MDKSA-2002-016.php
http://www.iss.net/security_center/static/8258.php
http://www.caldera.com/support/security/advisories/CSSA-2002-010.0.txt
http://marc.info/?l=bugtraq&m=101443252627021&w=2
http://marc.info/?l=bugtraq&m=101440163111826&w=2
http://marc.info/?l=bugtraq&m=101431040422095&w=2
http://distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000464
http://archives.neohapsis.com/archives/linux/caldera/2002-q1/0014.html