darkfish.js in RDoc 2.3.0 through 3.12 and 4.x before 4.0.0.preview2.1, as used in Ruby, does not properly generate documents, which allows remote attackers to conduct cross-site scripting (XSS) attacks via a crafted URL.
Ruby (aka CRuby) 1.9 before 1.9.3-p327 and 2.0 before r37575 computes hash values without properly restricting the ability to trigger hash collisions predictably, which allows context-dependent attackers to cause a denial of service (CPU consumption) via crafted input to an application that maintains a hash table, as demonstrated by a universal multicollision attack against a variant of the MurmurHash2 algorithm, a different vulnerability than CVE-2011-4815.
The SecureRandom.random_bytes function in lib/securerandom.rb in Ruby before 1.8.7-p352 and 1.9.x before 1.9.2-p290 relies on PID values for initialization, which makes it easier for context-dependent attackers to predict the result string by leveraging knowledge of random strings obtained in an earlier process with the same PID.
The VpMemAlloc function in bigdecimal.c in the BigDecimal class in Ruby 1.9.2-p136 and earlier, as used on Apple Mac OS X before 10.6.7 and other platforms, does not properly allocate memory, which allows context-dependent attackers to execute arbitrary code or cause a denial of service (application crash) via vectors involving creation of a large BigDecimal value within a 64-bit process, related to an "integer truncation issue."
The FileUtils.remove_entry_secure method in Ruby 1.8.6 through 1.8.6-420, 1.8.7 through 1.8.7-330, 1.8.8dev, 1.9.1 through 1.9.1-430, 1.9.2 through 1.9.2-136, and 1.9.3dev allows local users to delete arbitrary files via a symlink attack.