CVE-2015-4020

Description

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.

Category

4.3
CVSS
Severity: Medium
CVSS 2.0 •
EPSS 0.54%
Vendor Advisory rubygems.org Vendor Advisory rubygems.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
http://blog.rubygems.org/2015/06/08/2.2.5-released.html vendor advisory
https://www.trustwave.com/Resources/SpiderLabs-Blog/Attacking-Ruby-Gem-Security-with-CVE-2015-3900/ third party advisory
http://www.securityfocus.com/bid/75431 vdb entry
https://www.trustwave.com/Resources/Security-Advisories/Advisories/TWSL2015-009/?fid=6478 third party advisory
http://blog.rubygems.org/2015/06/08/2.4.8-released.html vendor advisory
https://github.com/rubygems/rubygems/commit/5c7bfb5
https://puppet.com/security/cve/CVE-2015-3900
http://www.oracle.com/technetwork/topics/security/bulletinoct2015-2511968.html third party advisory

Frequently Asked Questions

What is the severity of CVE-2015-4020?
CVE-2015-4020 has been scored as a medium severity vulnerability.
How to fix CVE-2015-4020?
To fix CVE-2015-4020, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2015-4020 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2015-4020 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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