Which versions of biunldler are malicious?

The following RubyGems versions of biunldler are flagged malicious: 1.0.0, 1.0.58276. Treat any of these as compromised.

How do I remediate biunldler if I installed it?

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

If biunldler 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 biunldler part of a known attack campaign?

Yes — biunldler is associated with the RLMA-2026-07361 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 biunldler across my projects, lockfiles, and CI pipelines?

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

Malicious package

biunldlerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

biunldler is a confirmed malicious RubyGems package (MAL-2026-16697) that executes malicious code on install (malicious versions 1.0.0, 1.0.58276). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in biunldler (RubyGems)

MAL-2026-16697

Immediate action

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

gem uninstall biunldler

Malicious versions

2 flagged

1.0.01.0.58276

Indicators of compromise (SHA-256)

031af3a5fe1d6add732f1af3a124959ccdd7432369cf01ea38db42e24a847a7c

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for biunldler (2 malicious versions).
If you installed it — respond
Remove biunldler 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 biunldler 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. biunldler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.58276 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07361

Credits

ReversingLabs · finder

Detect & block this

O3 blocks biunldler-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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