Which versions of bumdlern are malicious?

The following RubyGems versions of bumdlern are flagged malicious: 1.0.0, 1.0.94748. Treat any of these as compromised.

How do I remediate bumdlern if I installed it?

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

If bumdlern 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 bumdlern part of a known attack campaign?

Yes — bumdlern is associated with the RLMA-2026-07536 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 bumdlern across my projects, lockfiles, and CI pipelines?

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

Malicious package

bumdlernRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bumdlern is a confirmed malicious RubyGems package (MAL-2026-16850) that executes malicious code on install (malicious versions 1.0.0, 1.0.94748). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bumdlern (RubyGems)

MAL-2026-16850

Immediate action

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

gem uninstall bumdlern

Malicious versions

2 flagged

1.0.01.0.94748

Indicators of compromise (SHA-256)

9e37e296fe22b4f367b4a187a701e34e9db7425047dbbd39352d6983e0ae8345

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bumdlern (2 malicious versions).
If you installed it — respond
Remove bumdlern 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 bumdlern 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. bumdlern on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.94748 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07536

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bumdlern-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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