Which versions of bumdleo are malicious?

The following RubyGems versions of bumdleo are flagged malicious: 1.0.0, 1.0.35386. Treat any of these as compromised.

How do I remediate bumdleo if I installed it?

Remove bumdleo 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 bumdleo — how do I know if it already compromised me?

If bumdleo 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 bumdleo part of a known attack campaign?

Yes — bumdleo is associated with the RLMA-2026-07525 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 bumdleo across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for bumdleo (2 malicious versions).

Malicious package

bumdleoRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bumdleo is a confirmed malicious RubyGems package (MAL-2026-16839) that executes malicious code on install (malicious versions 1.0.0, 1.0.35386). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bumdleo (RubyGems)

MAL-2026-16839

Immediate action

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

gem uninstall bumdleo

Malicious versions

2 flagged

1.0.01.0.35386

Indicators of compromise (SHA-256)

037fbbd385bd2ce432ba31640dff6baf24348292bd7ff9cfedb81234273f11be

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bumdleo (2 malicious versions).
If you installed it — respond
Remove bumdleo 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 bumdleo 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. bumdleo on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.35386 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07525

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bumdleo-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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