net6: multiple vulnerabilities

Vasiliy Kulikov reported that libnet6 did not check the basic_server::id_counter for integer overflows. This number is used to distinguish different users, so an attacker that was able to open UINT_MAX successive connections could get an identifier of an already existing connection, allowing them to hijack that user's connection. (CVE-2011-4093)

Red Hat bugzilla:

Vasiliy Kulikov reported that libnet6 would check for user color collisions prior to authentication. This could allow for the disclosure of certain user information by users that were not authenticated. (CVE-2011-4091)