DL::dlopen in Ruby 1.8, 1.9.0, 1.9.2, 1.9.3, 2.0.0 before patchlevel 648, and 2.1 before 2.1.8 opens libraries with tainted names.

RubyGems 2.0.x before 2.0.16, 2.2.x before 2.2.4, and 2.4.x before 2.4.7 does not validate the hostname when fetching gems or making API requests, which allows remote attackers to redirect requests to arbitrary domains via a crafted DNS SRV record, aka a "DNS hijack attack."

The REXML parser in Ruby 1.9.x before 1.9.3 patchlevel 551, 2.0.x before 2.0.0 patchlevel 598, and 2.1.x before 2.1.5 allows remote attackers to cause a denial of service (CPU and memory consumption) a crafted XML document containing an empty string in an entity that is used in a large number of nested entity references, aka an XML Entity Expansion (XEE) attack. NOTE: this vulnerability exists because of an incomplete fix for CVE-2013-1821 and CVE-2014-8080.

The REXML parser in Ruby 1.9.x before 1.9.3-p550, 2.0.x before 2.0.0-p594, and 2.1.x before 2.1.4 allows remote attackers to cause a denial of service (memory consumption) via a crafted XML document, aka an XML Entity Expansion (XEE) attack.

Heap-based buffer overflow in Ruby 1.8, 1.9 before 1.9.3-p484, 2.0 before 2.0.0-p353, 2.1 before 2.1.0 preview2, and trunk before revision 43780 allows context-dependent attackers to cause a denial of service (segmentation fault) and possibly execute arbitrary code via a string that is converted to a floating point value, as demonstrated using (1) the to_f method or (2) JSON.parse.

(1) DL and (2) Fiddle in Ruby 1.9 before 1.9.3 patchlevel 426, and 2.0 before 2.0.0 patchlevel 195, do not perform taint checking for native functions, which allows context-dependent attackers to bypass intended $SAFE level restrictions.

Algorithmic complexity vulnerability in Gem::Version::VERSION_PATTERN in lib/rubygems/version.rb in RubyGems before 1.8.23.1, 1.8.24 through 1.8.25, 2.0.x before 2.0.8, and 2.1.x before 2.1.0, as used in Ruby 1.9.0 through 2.0.0p247, allows remote attackers to cause a denial of service (CPU consumption) via a crafted gem version that triggers a large amount of backtracking in a regular expression.

Algorithmic complexity vulnerability in Gem::Version::ANCHORED_VERSION_PATTERN in lib/rubygems/version.rb in RubyGems before 1.8.23.2, 1.8.24 through 1.8.26, 2.0.x before 2.0.10, and 2.1.x before 2.1.5, as used in Ruby 1.9.0 through 2.0.0p247, allows remote attackers to cause a denial of service (CPU consumption) via a crafted gem version that triggers a large amount of backtracking in a regular expression. NOTE: this issue is due to an incomplete fix for CVE-2013-4287.

The OpenSSL::SSL.verify_certificate_identity function in lib/openssl/ssl.rb in Ruby 1.8 before 1.8.7-p374, 1.9 before 1.9.3-p448, and 2.0 before 2.0.0-p247 does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.

Ruby 1.8.7 before patchlevel 371, 1.9.3 before patchlevel 286, and 2.0 before revision r37068 allows context-dependent attackers to bypass safe-level restrictions and modify untainted strings via the name_err_mesg_to_str API function, which marks the string as tainted, a different vulnerability than CVE-2011-1005.