RubyGems could be made to download and install malicious gem files.
John Firebaugh discovered that the RubyGems remote gem fetcher did not properly verify SSL certificates. A remote attacker could exploit this to perform a man in the middle attack to alter gem files being downloaded for installation. (CVE-2012-2126)
26 September 2012
A security issue affects these releases of Ubuntu and its derivatives:
RubyGems could be made to download and install malicious gem files.
John Firebaugh discovered that the RubyGems remote gem fetcher did not properly verify SSL certificates. A remote attacker could exploit this to perform a man in the middle attack to alter gem files being downloaded for installation. (CVE-2012-2126)
John Firebaugh discovered that the RubyGems remote gem fetcher allowed redirection from HTTPS to HTTP. A remote attacker could exploit this to perform a man in the middle attack to alter gem files being downloaded for installation. (CVE-2012-2125)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.
Vulmon