CVE-2019-16782

There’s a possible information leak / session hijack vulnerability in Rack
(RubyGem rack). This vulnerability is patched in versions 1.6.12 and 2.0.8.
Attackers may be able to find and hijack sessions by using timing attacks
targeting the session id. Session ids are usually stored and indexed in a
database that uses some kind of scheme for speeding up lookups of that
session id. By carefully measuring the amount of time it takes to look up a
session, an attacker may be able to find a valid session id and hijack the
session. The session id itself may be generated randomly, but the way the
session is indexed by the backing store does not use a secure comparison.

Bugs

• <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=946983&gt;