CVE-2015-4020

mediumpriority · track · 18EPSS 0.035 · 89 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

3.46% (89th) EPSS

CVSS 4.3 · medium

Is it mine?

35 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

4.3

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.7–4.3

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v2.03.7lowAV:N/AC:M/Au:N/C:N/I:P/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimaryCWE-20US

affected products (35)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
oracle solaris= 11.3nvdUScpe:2.3:o:oracle:solaris:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.0nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.1nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.10nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.11nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.12nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.13nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.14nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.15nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.16nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.2nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.3nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.4nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.5nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.6nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.7nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.8nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.0.9nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*
rubygems rubygems= 2.2.0nvdUScpe:2.3:a:rubygems:rubygems:*:*:*:*:*:*:*:*

showing 20 of 35

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-qv62-xfj6-32xmRubyGems Improper Input Validation vulnerability2022-05-17ghsa · osvUS
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.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv NVD CVE.org MITRE

published 2015-08-25modified 2026-06-17

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+25188 more

references (22)

External citations — patches, advisories, analysis.

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