Which versions of biumdler are malicious?

The following RubyGems versions of biumdler are flagged malicious: 1.0.0, 1.0.23058. Treat any of these as compromised.

How do I remediate biumdler if I installed it?

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

If biumdler 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 biumdler part of a known attack campaign?

Yes — biumdler is associated with the RLMA-2026-07288 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 biumdler across my projects, lockfiles, and CI pipelines?

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

Malicious package

biumdlerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

biumdler is a confirmed malicious RubyGems package (MAL-2026-16624) that executes malicious code on install (malicious versions 1.0.0, 1.0.23058). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in biumdler (RubyGems)

MAL-2026-16624

Immediate action

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

gem uninstall biumdler

Malicious versions

2 flagged

1.0.01.0.23058

Indicators of compromise (SHA-256)

a699f8fccd1b8cc0f5c762efb3682657a45510c7d3ad7c323340fa42af2389ff

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for biumdler (2 malicious versions).
If you installed it — respond
Remove biumdler 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 biumdler 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. biumdler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.23058 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07288

Credits

ReversingLabs · finder

Detect & block this

O3 blocks biumdler-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

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