libjson-ruby - security update

The JSON gem for Ruby allowed remote attackers to cause a denial of
service (resource consumption) or bypass the mass assignment protection
mechanism via a crafted JSON document that triggers the creation of
arbitrary Ruby symbols or certain internal objects, as demonstrated by
conducting a SQL injection attack against Ruby on Rails, aka “Unsafe
Object Creation Vulnerability.”

For Debian 6 Squeeze, this issue has been fixed in libjson-ruby
version 1.1.9-1+deb6u1.