Debian DSA-2783-1 : librack-ruby - several vulnerabilities
Medium Nessus Plugin ID 70534
The remote Debian host is missing a security-related update.
Several vulnerabilities were discovered in Rack, a modular Ruby webserver interface. The Common Vulnerabilites and Exposures project identifies the following vulnerabilities : - CVE-2011-5036 Rack computes hash values for form parameters without restricting the ability to trigger hash collisions predictably, which allows remote attackers to cause a denial of service (CPU consumption) by sending many crafted parameters. - CVE-2013-0183 A remote attacker could cause a denial of service (memory consumption and out-of-memory error) via a long string in a Multipart HTTP packet. - CVE-2013-0184 A vulnerability in Rack::Auth::AbstractRequest allows remote attackers to cause a denial of service via unknown vectors. - CVE-2013-0263 Rack::Session::Cookie allows remote attackers to guess the session cookie, gain privileges, and execute arbitrary code via a timing attack involving an HMAC comparison function that does not run in constant time.
Upgrade the librack-ruby packages. For the oldstable distribution (squeeze), these problems have been fixed in version 1.1.0-4+squeeze1. The stable, testing and unstable distributions do not contain the librack-ruby package. They have already been addressed in version 1.4.1-2.1 of the ruby-rack package.