Malicious code in w002yardprobe (RubyGems)
Published Sources: OSV (Schadpakete)
- Malicious package
What is affected, what to do
Uninstall the package, isolate affected environments and rotate credentials that were available during installation.
Not sure whether and how you are affected? Ask a question about this vulnerability
Malicious package
RubyGemsw002yardprobe
“w002yardprobe” is registered as malicious in the RubyGems repository. Anyone who installed the package should uninstall it immediately, isolate affected environments and rotate credentials that were present during installation.
Affected versions (2)
- 0.0.4
- 0.0.5
purl: pkg:gem/w002yardprobe
Sources (2)
amazon-inspector
IN-MAL-2026-022534Versions from this source: 0.0.4
sha256: 5252a1d5dd27d6e0edd3c1fc3936ff09d93b2fcc8e5544afc09fe7fb7d90bee5
amazon-inspector
IN-MAL-2026-022533Versions from this source: 0.0.5
sha256: 721580f8eda44ad5ee7604f5ba0648e8830302f784e3e4a995e02ca7359c909e
The OSSF `malicious-packages` namespace lists packages flagged as malicious by static analysis or sandbox detonation. An entry here is a confirmed finding, not a suspicion.
Metrics
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Priority
No value is available for this vulnerability.
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CVSS v3
No value is available for this vulnerability.
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EPSS score
No value is available for this vulnerability.
Show all metrics
- Severity
- High
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 30.00 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- no public PoC known
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
-= Per source details. Do not edit below this line.=-
Source: amazon-inspector (721580f8eda44ad5ee7604f5ba0648e8830302f784e3e4a995e02ca7359c909e)
The gem ships a .yardopts file containing --load./script.rb, which causes YARD to execute script.rb whenever documentation is generated for the gem (locally via yard doc, in CI, or on doc-hosting services such as RubyDoc.info). script.rb collects host identifiers — Socket.gethostname, current working directory, UID, and RUBY_VERSION — and POSTs them via Net::HTTP.post_form to the hardcoded third-party collector https://webhook.site/97fa3c6a-3fad-4d2d-8312-15dc37e41e66. The same script also rewrites lib/w002yardprobe.rb in place (substituting a MARKSLOT token with a runtime stamp) and drops sentinel files W002SCRIPT_RAN.txt and W002EGRESS_OK.txt in the detected build directory (e.g. /build), indicating the gem is instrumented to probe a documentation-build sandbox. The package self-identifies as a probe; the exfiltration and build-environment mutation are the gem's purpose. The trigger is YARD doc generation rather than gem install or require, so the harm materializes against whichever host (developer workstation, CI runner, or doc-hosting pipeline) processes the gem's documentation.