Tor before 0.2.0.32 does not properly process the ClientDNSRejectInternalAddresses configuration option in situations where an exit relay issues a policy-based refusal of a stream, which allows remote exit relays to have an unknown impact by mapping an internal IP address to the destination hostname of a refused stream.
https://exchange.xforce.ibmcloud.com/vulnerabilities/47102
http://www.vupen.com/english/advisories/2008/3366
http://www.securityfocus.com/bid/32648
http://security.gentoo.org/glsa/glsa-200904-11.xml
http://secunia.com/advisories/34583