Which versions of biunrdler are malicious?

The following RubyGems versions of biunrdler are flagged malicious: 1.0.0, 1.0.63228. Treat any of these as compromised.

How do I remediate biunrdler if I installed it?

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

If biunrdler 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 biunrdler part of a known attack campaign?

Yes — biunrdler is associated with the RLMA-2026-07366 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 biunrdler across my projects, lockfiles, and CI pipelines?

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

Malicious package

biunrdlerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

biunrdler is a confirmed malicious RubyGems package (MAL-2026-16702) that executes malicious code on install (malicious versions 1.0.0, 1.0.63228). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in biunrdler (RubyGems)

MAL-2026-16702

Immediate action

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

gem uninstall biunrdler

Malicious versions

2 flagged

1.0.01.0.63228

Indicators of compromise (SHA-256)

e5a712337908e028e923b9798671237518f0fcb3c8fcceaf2d6386cac31a3c08

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for biunrdler (2 malicious versions).
If you installed it — respond
Remove biunrdler 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 biunrdler 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. biunrdler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.63228 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07366

Credits

ReversingLabs · finder

Detect & block this

O3 blocks biunrdler-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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