Which versions of biundeler are malicious?

The following RubyGems versions of biundeler are flagged malicious: 1.0.0, 1.0.85614. Treat any of these as compromised.

How do I remediate biundeler if I installed it?

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

If biundeler 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 biundeler part of a known attack campaign?

Yes — biundeler is associated with the RLMA-2026-07296 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 biundeler across my projects, lockfiles, and CI pipelines?

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

Malicious package

biundelerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

biundeler is a confirmed malicious RubyGems package (MAL-2026-16632) that executes malicious code on install (malicious versions 1.0.0, 1.0.85614). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in biundeler (RubyGems)

MAL-2026-16632

Immediate action

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

gem uninstall biundeler

Malicious versions

2 flagged

1.0.01.0.85614

Indicators of compromise (SHA-256)

6eb9cee192eee560669b422eb59b7d64b3459cf6bee667f58f2d1bae05e61d2f

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for biundeler (2 malicious versions).
If you installed it — respond
Remove biundeler 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 biundeler 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. biundeler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.85614 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07296

Credits

ReversingLabs · finder

Detect & block this

O3 blocks biundeler-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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