Which versions of defi-yield-calculator are malicious?

The following RubyGems versions of defi-yield-calculator are flagged malicious: 0.9.1. Treat any of these as compromised.

How do I remediate defi-yield-calculator if I installed it?

defi-yield-calculator is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.

I already installed defi-yield-calculator — how do I know if it already compromised me?

If defi-yield-calculator was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.

Is defi-yield-calculator part of a known attack campaign?

Yes — defi-yield-calculator is associated with the IN-MAL-2026-021347 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find defi-yield-calculator across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for defi-yield-calculator (version 0.9.1).

Malicious package

defi-yield-calculatorRubyGems

Advisory published Oct 11, 2026Updated Oct 11, 2026

defi-yield-calculator is a confirmed malicious RubyGems package (MAL-2026-17783) that steals credentials and exfiltrates sensitive data (malicious version 0.9.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in defi-yield-calculator (RubyGems)

MAL-2026-17783

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

gem uninstall defi-yield-calculator

What this malware does

The gem ships an ext/extconf.rb that base64-decodes an embedded Ruby payload and runs it via eval inside a double-forked, detached, stdio-nulled background process after a 20–40 minute sleep. Execution is gated by anti-analysis checks that skip CI runners, ephemeral/sandbox hostnames, generated analyst usernames, common analysis working directories, low-uptime hosts, and hosts missing developer artifacts (~/.ssh, ~/.gitconfig, ~/.gem/credentials, ~/.bundle, ~/.npmrc), so the payload only fires on real developer machines. The decoded payload opens a TCPSocket to the hardcoded host 45.138.12.177 on port 8089 and bidirectionally pipes it to /bin/sh in an infinite reconnect loop, giving a remote operator persistent interactive shell access to the installer's host. The gemspec presents the package as a 'defi yield calculator' with a trivial lib stub exposing only VERSION/build_id/healthy?, the README is copied from an unrelated 'bitcoin-rpc-lite' project, and create_makefile targets 'bitcoin_rpc_lite_native' despite no C/C++ sources being shipped — the native-extension declaration exists solely to trigger the dropper during gem install.

Malicious versions

1 flagged

0.9.1

Indicators of compromise (SHA-256)

ee8b3e50479b61d2ff6e2f5a19de20473cf8fc3c91f99945aff51f112a617192

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for defi-yield-calculator (version 0.9.1).
If you installed it — respond
defi-yield-calculator is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If defi-yield-calculator was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.

Frequently asked questions

No. defi-yield-calculator on RubyGems has been identified as a malicious package (version 0.9.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-021347

References

rubygems.org

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks defi-yield-calculator-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

Explore

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