The mail function in PHP 4.x to 4.2.2 does not filter ASCII control characters from its arguments, which could allow remote attackers to modify mail message content, including mail headers, and possibly use PHP as a "spam proxy."
https://exchange.xforce.ibmcloud.com/vulnerabilities/9959
http://www.securityfocus.com/bid/5562
http://www.redhat.com/support/errata/RHSA-2003-159.html
http://www.redhat.com/support/errata/RHSA-2002-248.html
http://www.redhat.com/support/errata/RHSA-2002-244.html
http://www.redhat.com/support/errata/RHSA-2002-243.html
http://www.redhat.com/support/errata/RHSA-2002-214.html
http://www.redhat.com/support/errata/RHSA-2002-213.html
http://www.novell.com/linux/security/advisories/2002_036_modphp4.html
http://www.mandrakesoft.com/security/advisories?name=MDKSA-2003:082
http://www.kb.cert.org/vuls/id/410609
http://www.debian.org/security/2002/dsa-168
http://marc.info/?l=bugtraq&m=105760591228031&w=2
http://marc.info/?l=bugtraq&m=103011916928204&w=2
http://distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000545