Input validation error in Ruby - CVE-2015-4020
Published: August 25, 2015 / Updated: July 28, 2020
Ruby
Detailed vulnerability description
The vulnerability allows a remote non-authenticated attacker to manipulate data.
RubyGems 2.0.x before 2.0.17, 2.2.x before 2.2.5, and 2.4.x before 2.4.8 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 with a domain that is suffixed with the original domain name, aka a "DNS hijack attack." NOTE: this vulnerability exists because to an incomplete fix for CVE-2015-3900.
How to mitigate CVE-2015-4020
Sources
- http://blog.rubygems.org/2015/06/08/2.2.5-released.html
- http://blog.rubygems.org/2015/06/08/2.4.8-released.html
- http://www.oracle.com/technetwork/topics/security/bulletinoct2015-2511968.html
- http://www.securityfocus.com/bid/75431
- https://github.com/rubygems/rubygems/commit/5c7bfb5
- https://puppet.com/security/cve/CVE-2015-3900
- https://www.trustwave.com/Resources/Security-Advisories/Advisories/TWSL2015-009/?fid=6478
- https://www.trustwave.com/Resources/SpiderLabs-Blog/Attacking-Ruby-Gem-Security-with-CVE-2015-3900/