RubyGems is the Ruby standard for publishing and managing third-party libraries. It was found that RubyGems did not verify SSL connections. This could lead to man-in-the-middle attacks. It was found that, when using RubyGems, the connection could be redirected from HTTPS to HTTP. This could lead to a user believing they are installing a gem via HTTPS, when the connection may have been silently downgraded to HTTP. It was discovered that the rubygems API validated version strings using an unsafe regular expression. An application making use of this API to process a version string from an untrusted source could be vulnerable to a denial of service attack through CPU exhaustion. Red Hat would like to thank Rubygems upstream for reporting CVE-2013-4287. Upstream acknowledges Damir Sharipov as the original reporter. All rubygems users are advised to upgrade to this updated package, which contains backported patches to correct these issues.