Which versions of biundoler are malicious?

The following RubyGems versions of biundoler are flagged malicious: 1.0.0, 1.0.85319. Treat any of these as compromised.

How do I remediate biundoler if I installed it?

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

If biundoler 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 biundoler part of a known attack campaign?

Yes — biundoler is associated with the RLMA-2026-07350 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 biundoler across my projects, lockfiles, and CI pipelines?

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

Malicious package

biundolerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

biundoler is a confirmed malicious RubyGems package (MAL-2026-16686) that executes malicious code on install (malicious versions 1.0.0, 1.0.85319). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in biundoler (RubyGems)

MAL-2026-16686

Immediate action

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

gem uninstall biundoler

Malicious versions

2 flagged

1.0.01.0.85319

Indicators of compromise (SHA-256)

f1eeacf0c3455d0ba8c38dcc6c03352eac4e80dfc8f07897ced3bd027e447187

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for biundoler (2 malicious versions).
If you installed it — respond
Remove biundoler 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 biundoler 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. biundoler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.85319 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07350

Credits

ReversingLabs · finder

Detect & block this

O3 blocks biundoler-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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