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 req
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.
- Published
- Aug 25, 2015
- Updated
- Jun 16, 2026
- EPSS
- 3.5% · 89th percentile
- CWE
- CWE-20
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Report tools
Action score
18
Monitor
Low priority for now.
- CVSS
- 17 / 40 · 4.3 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 3.5%
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- oracle solaris11.3
- rubygems rubygems2.0.0
- rubygems rubygems2.0.1
- rubygems rubygems2.0.10
- rubygems rubygems2.0.11
- rubygems rubygems2.0.12
- rubygems rubygems2.0.13
- rubygems rubygems2.0.14
- rubygems rubygems2.0.15
- rubygems rubygems2.0.16
- rubygems rubygems2.0.2
- rubygems rubygems2.0.3
- rubygems rubygems2.0.4
- rubygems rubygems2.0.5
- rubygems rubygems2.0.6
- rubygems rubygems2.0.7
- rubygems rubygems2.0.8
- rubygems rubygems2.0.9
- rubygems rubygems2.2.0
- rubygems rubygems2.2.1
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| RubyGems | rubygems-update | from 2.1.0.rc.1 · before 2.2.5 | 2.2.5 |
| RubyGems | rubygems-update | from 2.3.0 · before 2.4.8 | 2.4.8 |
| RubyGems | rubygems-update | before 2.0.17 | 2.0.17 |
Same product
rubygems: all recordsOther highest-scoring records for the same primary product.
- CVE-2017-0903RubyGems versions between 2.0.0 and 2.6.13 are vulnerable to a possible remote code execution vulnerability.44Plan
- CVE-2017-0899RubyGems version 2.6.12 and earlier is vulnerable to maliciously crafted gem specifications that include terminal escape characters.42Plan
- CVE-2018-1000076RubyGems version Ruby 2.2 series: 2.2.9 and earlier, Ruby 2.3 series: 2.3.6 and earlier, Ruby 2.4 series: 2.4.3 and earlier, Ruby 2.5 series40Plan
- CVE-2017-0901RubyGems version 2.6.12 and earlier fails to validate specification names, allowing a maliciously crafted gem to potentially overwrite any f39Monitor
- CVE-2019-8324An issue was discovered in RubyGems 2.6 and later through 3.0.2.36Monitor
- CVE-2022-36073RubyGems allows creation of users with arbitrary unverified emails35Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| RubyGems:rubygems-update | 2.0.17 | Package registry (OSV) |
| RubyGems:rubygems-update | 2.2.5 | Package registry (OSV) |
| RubyGems:rubygems-update | 2.4.8 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
- RubyGemsHackerOne · disclosure only (VDP) · rubygems/rubygems
- RubyGemsHackerOne · disclosure only (VDP)
The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.
Technical details
Attack conditions
If successful
- Confidentiality
- none
- Integrity
- P · data or configuration can be modified
- Availability
- none
- Attack complexity
- M
- Confidentiality impact
- None
- Integrity impact
- P
- Availability impact
- None
Weakness class (CWE)
CWE-20 · Improper Input ValidationCVSS vector
AV:N/AC:M/Au:N/C:N/I:P/A:N
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Buffer Overflow via Environment VariablesCAPEC-10likelihood: High · High
- Server Side Include (SSI) InjectionCAPEC-101likelihood: High · High
- Cross Zone ScriptingCAPEC-104likelihood: Medium · High
- Command Line Execution through SQL InjectionCAPEC-108likelihood: Low · Very High
- Object Relational Mapping InjectionCAPEC-109likelihood: Low · High
- SQL Injection through SOAP Parameter TamperingCAPEC-110likelihood: High · Very High
- Double EncodingCAPEC-120likelihood: Low · Medium
- Subverting Environment Variable ValuesCAPEC-13likelihood: High · Very High
ATT&CK techniques
- Obfuscated Files or InformationT1027
- Masquerading: Invalid Code SignatureT1036.001
- Steal Web Session CookieT1539
- Subvert Trust Controls: Code SigningT1553.002
- Impair Defenses:Impair Command History LoggingT1562.003
- Hijack Execution Flow:Dynamic Linker HijackingT1574.006
- Hijack Execution Flow:Path Interception by PATH Environment VariableT1574.007
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- blog.rubygems.org/2015/06/08/2.2.5-released.html
- blog.rubygems.org/2015/06/08/2.4.8-released.html
- www.oracle.com/technetwork/topics/security/bulletinoct2015-2511968.html
- www.securityfocus.com/bid/75431
- github.com/rubygems/rubygems/commit/5c7bfb5
- puppet.com/security/cve/CVE-2015-3900
- www.trustwave.com/Resources/Security-Advisories/Advisories/TWSL2015-009/?fid=6478
- www.trustwave.com/Resources/SpiderLabs-Blog/Attacking-Ruby-Gem-Security-with-CVE-2015-3900/
Vendor advisories and official records. Exploit/PoC links are deliberately left out.