Which versions of rfetch4 are malicious?

The following RubyGems versions of rfetch4 are flagged malicious: 0.0.1. Treat any of these as compromised.

How do I remediate rfetch4 if I installed it?

Remove rfetch4 from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.

I already installed rfetch4 — how do I know if it already compromised me?

If rfetch4 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 rfetch4 part of a known attack campaign?

Yes — rfetch4 is associated with the RLMA-2026-03164, RLUA-2026-09051 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 rfetch4 across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for rfetch4 (version 0.0.1).

Malicious package

rfetch4RubyGems

Advisory published Jul 7, 2026Updated Sep 24, 2026

rfetch4 is a confirmed malicious RubyGems package (MAL-2026-8513) that executes malicious code on install (malicious version 0.0.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in rfetch4 (RubyGems)

MAL-2026-8513

Immediate action

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

gem uninstall rfetch4

Malicious versions

1 flagged

0.0.1

Indicators of compromise (SHA-256)

2f54595ec5b81f6b1ac000e79d656b2da82a473e1c26154d5ee89d7636c937c8

ef6a657073e38ea6d949e9f133f829878bd3209837c745ca8bdf5ec8a56d7035

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for rfetch4 (version 0.0.1).
If you installed it — respond
Remove rfetch4 from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If rfetch4 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. rfetch4 on RubyGems has been identified as a malicious package (version 0.0.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-03164RLUA-2026-09051

References

github.com

Credits

ReversingLabs · finder

Detect & block this

O3 blocks rfetch4-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.

Malware detection Runtime egress monitoring

Explore

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