Which versions of biundeer are malicious?

The following RubyGems versions of biundeer are flagged malicious: 1.0.0, 1.0.11827. Treat any of these as compromised.

How do I remediate biundeer if I installed it?

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

If biundeer 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 biundeer part of a known attack campaign?

Yes — biundeer is associated with the RLMA-2026-07295 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 biundeer across my projects, lockfiles, and CI pipelines?

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

Malicious package

biundeerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

biundeer is a confirmed malicious RubyGems package (MAL-2026-16631) that executes malicious code on install (malicious versions 1.0.0, 1.0.11827). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in biundeer (RubyGems)

MAL-2026-16631

Immediate action

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

gem uninstall biundeer

Malicious versions

2 flagged

1.0.01.0.11827

Indicators of compromise (SHA-256)

40abaaa35973a81e966a13a473a29d6777eeed759703ac69e363e4e5283b129f

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for biundeer (2 malicious versions).
If you installed it — respond
Remove biundeer 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 biundeer 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. biundeer on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.11827 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07295

Credits

ReversingLabs · finder

Detect & block this

O3 blocks biundeer-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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