Which versions of buenlder are malicious?

The following RubyGems versions of buenlder are flagged malicious: 1.0.0, 1.0.41769. Treat any of these as compromised.

How do I remediate buenlder if I installed it?

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

If buenlder 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 buenlder part of a known attack campaign?

Yes — buenlder is associated with the RLMA-2026-07473 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 buenlder across my projects, lockfiles, and CI pipelines?

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

Malicious package

buenlderRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

buenlder is a confirmed malicious RubyGems package (MAL-2026-16788) that executes malicious code on install (malicious versions 1.0.0, 1.0.41769). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in buenlder (RubyGems)

MAL-2026-16788

Immediate action

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

gem uninstall buenlder

Malicious versions

2 flagged

1.0.01.0.41769

Indicators of compromise (SHA-256)

cc4873e272eb9176a2d5ddd2fe64f6d8ac91dfd98b8d5043d09fefb89493fe15

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for buenlder (2 malicious versions).
If you installed it — respond
Remove buenlder 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 buenlder 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. buenlder on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.41769 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07473

Credits

ReversingLabs · finder

Detect & block this

O3 blocks buenlder-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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