The CGI module in Ruby 1.6 before 1.6.8, and 1.8 before 1.8.2, allows remote attackers to cause a denial of service (infinite loop and CPU consumption) via a certain HTTP request.

The FileStore capability in CGI::Session for Ruby before 1.8.1, and possibly PStore, creates files with insecure permissions, which can allow local users to steal session information and hijack sessions.

Ruby 1.6.x up to 1.6.8, 1.8.x up to 1.8.2, and 1.9.0 development up to 2005-09-01 allows attackers to bypass safe level and taint flag protections and execute disallowed code when Ruby processes a program through standard input (stdin).

The HTTP/XMLRPC server in Ruby before 1.8.2 uses blocking sockets, which allows attackers to cause a denial of service (blocked connections) via a large amount of data.