Amazon Linux 1 Security Advisory: ALAS-2015-547
Advisory Release Date: 2015-06-16 10:30 Pacific
Advisory Updated Date: 2015-06-18 20:44 Pacific
RubyGems provides the ability of a domain to direct clients to a separate host that is used to fetch gems and make API calls against. This mechanism is implemented via DNS, specificly a SRV record _rubygems._tcp under the original requested domain. RubyGems did not validate the hostname returned in the SRV record before sending requests to it. (CVE-2015-3900)
As discussed upstream (https://www.trustwave.com/Resources/Security-Advisories/Advisories/TWSL2015-009/?fid=6478), CVE-2015-4020 is due to an incomplete fix for CVE-2015-3900, which allowed redirection to an arbitrary gem server in any security domain.
Affected Packages:
ruby20
Issue Correction:
Run yum update ruby20 to update your system.
i686:
ruby20-2.0.0.645-1.27.amzn1.i686
ruby20-devel-2.0.0.645-1.27.amzn1.i686
ruby20-debuginfo-2.0.0.645-1.27.amzn1.i686
rubygem20-io-console-0.4.2-1.27.amzn1.i686
rubygem20-bigdecimal-1.2.0-1.27.amzn1.i686
ruby20-libs-2.0.0.645-1.27.amzn1.i686
rubygem20-psych-2.0.0-1.27.amzn1.i686
noarch:
rubygems20-devel-2.0.14-1.27.amzn1.noarch
rubygems20-2.0.14-1.27.amzn1.noarch
ruby20-irb-2.0.0.645-1.27.amzn1.noarch
ruby20-doc-2.0.0.645-1.27.amzn1.noarch
src:
ruby20-2.0.0.645-1.27.amzn1.src
x86_64:
ruby20-debuginfo-2.0.0.645-1.27.amzn1.x86_64
rubygem20-psych-2.0.0-1.27.amzn1.x86_64
ruby20-libs-2.0.0.645-1.27.amzn1.x86_64
ruby20-devel-2.0.0.645-1.27.amzn1.x86_64
ruby20-2.0.0.645-1.27.amzn1.x86_64
rubygem20-bigdecimal-1.2.0-1.27.amzn1.x86_64
rubygem20-io-console-0.4.2-1.27.amzn1.x86_64