Which versions of buimdler are malicious?

The following RubyGems versions of buimdler are flagged malicious: 1.0.0, 1.0.2891. Treat any of these as compromised.

How do I remediate buimdler if I installed it?

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

If buimdler 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 buimdler part of a known attack campaign?

Yes — buimdler is associated with the RLMA-2026-07480 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 buimdler across my projects, lockfiles, and CI pipelines?

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

Malicious package

buimdlerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

buimdler is a confirmed malicious RubyGems package (MAL-2026-16795) that executes malicious code on install (malicious versions 1.0.0, 1.0.2891). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in buimdler (RubyGems)

MAL-2026-16795

Immediate action

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

gem uninstall buimdler

Malicious versions

2 flagged

1.0.01.0.2891

Indicators of compromise (SHA-256)

564c84e6371399a290409d5ef1ebe834233bde03813dc6b090ee4739f84c06ec

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for buimdler (2 malicious versions).
If you installed it — respond
Remove buimdler 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 buimdler 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. buimdler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.2891 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07480

Credits

ReversingLabs · finder

Detect & block this

O3 blocks buimdler-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

All malware advisories How O3 detects malware Vulnerability database