Which versions of biuncler are malicious?

The following RubyGems versions of biuncler are flagged malicious: 1.0.0, 1.0.92211. Treat any of these as compromised.

How do I remediate biuncler if I installed it?

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

If biuncler 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 biuncler part of a known attack campaign?

Yes — biuncler is associated with the RLMA-2026-07291 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 biuncler across my projects, lockfiles, and CI pipelines?

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

Malicious package

biunclerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

biuncler is a confirmed malicious RubyGems package (MAL-2026-16627) that executes malicious code on install (malicious versions 1.0.0, 1.0.92211). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in biuncler (RubyGems)

MAL-2026-16627

Immediate action

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

gem uninstall biuncler

Malicious versions

2 flagged

1.0.01.0.92211

Indicators of compromise (SHA-256)

53b71a109d00b509b0eb08f44f8c736490fa778a2714b14190d3addd39df6033

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for biuncler (2 malicious versions).
If you installed it — respond
Remove biuncler 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 biuncler 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. biuncler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.92211 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07291

Credits

ReversingLabs · finder

Detect & block this

O3 blocks biuncler-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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