The OpenID module in Drupal 7.x before 7.16 allows remote OpenID servers to read arbitrary files via a crafted DOCTYPE declaration in an XRDS file.
https://github.com/shacojx/Drupal-CVE-Exploit-POC
https://euvd.enisa.europa.eu/vulnerability/EUVD-2012-4482
http://www.openwall.com/lists/oss-security/2012/10/30/5
http://www.openwall.com/lists/oss-security/2012/10/29/4