CVE-2015-4020
MEDIUM severity · CVSS 4.3 · Improper input validation
4.3CVSS MEDIUM
Summary
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.
Impact & exploitability
Attack vectorNetwork
Attack complexity—
Privileges required—
User interaction—
Confidentiality impactNone
Integrity impact—
Availability impactNone
Exploit probability (EPSS)3%
AV:N/AC:M/Au:N/C:N/I:P/A:N
Affected products we track (1)
Recommendation
Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.
Additional information
- NVD record
- http://blog.rubygems.org/2015/06/08/2.2.5-released.htmlAdvisory
- http://blog.rubygems.org/2015/06/08/2.4.8-released.htmlAdvisory
- http://www.oracle.com/technetwork/topics/security/bulletinoct2015-2511968.htmlAdvisory
- 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=6478Advisory
- https://www.trustwave.com/Resources/SpiderLabs-Blog/Attacking-Ruby-Gem-Security-with-CVE-2015-3900/Advisory