Unspecified vulnerability in Rack::Auth::AbstractRequest in Rack 1.1.x before 1.1.5, 1.2.x before 1.2.7, 1.3.x before 1.3.9, and 1.4.x before 1.4.4 allows remote attackers to cause a denial of service via unknown vectors related to "symbolized arbitrary strings."

multipart/parser.rb in Rack 1.3.x before 1.3.8 and 1.4.x before 1.4.3 allows remote attackers to cause a denial of service (memory consumption and out-of-memory error) via a long string in a Multipart HTTP packet.

Rack::Session::Cookie in Rack 1.5.x before 1.5.2, 1.4.x before 1.4.5, 1.3.x before 1.3.10, 1.2.x before 1.2.8, and 1.1.x before 1.1.6 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.