CVE-2015-4020
RubyGems Improper Input Validation vulnerability
EPSS 0.52%
Description
RubyGems 2.0.x before 2.0.17, 2.2.x before 2.2.5, and 2.3.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 of an incomplete fix for CVE-2015-3900.
How to fix CVE-2015-4020
To remediate CVE-2015-4020, upgrade the affected package to a fixed version below.
- RubyGems/rubygems-update—upgrade to 2.0.17 or later
Is CVE-2015-4020 being exploited?
Low — EPSS is 0.5%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 2.0.17