Which versions of bumdlesr are malicious?

The following RubyGems versions of bumdlesr are flagged malicious: 1.0.0, 1.0.29696. Treat any of these as compromised.

How do I remediate bumdlesr if I installed it?

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

If bumdlesr 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 bumdlesr part of a known attack campaign?

Yes — bumdlesr is associated with the RLMA-2026-07540 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 bumdlesr across my projects, lockfiles, and CI pipelines?

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

Malicious package

bumdlesrRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bumdlesr is a confirmed malicious RubyGems package (MAL-2026-16854) that executes malicious code on install (malicious versions 1.0.0, 1.0.29696). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bumdlesr (RubyGems)

MAL-2026-16854

Immediate action

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

gem uninstall bumdlesr

Malicious versions

2 flagged

1.0.01.0.29696

Indicators of compromise (SHA-256)

0b0bd6271a75d294c6ecbe99f9b388c04914ab54751096fd80525a7aeff7c3f3

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bumdlesr (2 malicious versions).
If you installed it — respond
Remove bumdlesr 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 bumdlesr 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. bumdlesr on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.29696 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07540

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bumdlesr-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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