supply chain event / NVI-00009881 / Revision 1
Malicious code in etheremu.rb (RubyGems)
GitHub lists this malware advisory for etheremu.rb. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
etheremu.rb
source listed= 1.0.0
## Source: amazon-inspector (a82ac5d3f021ab23f4f461181f4150c12d672ef421b6f80c10dd8a307178442e) The gem's extconf.rb, executed automatically during `gem install`, contains a base64-encoded Ruby payload that is decoded and eval'd inside a detached forked process. The payload XOR-decodes a hardcoded bare-IP URL (http://45.138.12.177:8092/wgkit.tar.gz), downloads a tarball to /tmp/.w1.tgz over plain HTTP with no pinning or verification, extracts it, and executes the enclosed wg_install.sh via bash. The accompanying native extension C source is an empty stub whose Init function is a no-op, so the extension exists solely as a vehicle to trigger the dropper at install time. The dropper is wrapped in extensive anti-analysis gating: it exits early if CI environment variables are set, if the hostname matches sandbox/firecracker/vagrant patterns, if the username looks auto-generated or contains strings like 'sandbox', 'tester', 'analys', or 'scanner', if the current working directory is under /tmp, /var/tmp, /opt/rubygems, or /workspace, if machine uptime is under 1800 seconds, or if no developer dot-files are present. It further sleeps 20-40 minutes before firing. Execution is gated on the p
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-r55r-pjq3-j9f4 ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.