Which versions of biunfler are malicious?

The following RubyGems versions of biunfler are flagged malicious: 1.0.0, 1.0.95530. Treat any of these as compromised.

How do I remediate biunfler if I installed it?

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

If biunfler 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 biunfler part of a known attack campaign?

Yes — biunfler is associated with the RLMA-2026-07357 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 biunfler across my projects, lockfiles, and CI pipelines?

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

Malicious package

biunflerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

biunfler is a confirmed malicious RubyGems package (MAL-2026-16693) that executes malicious code on install (malicious versions 1.0.0, 1.0.95530). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in biunfler (RubyGems)

MAL-2026-16693

Immediate action

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

gem uninstall biunfler

Malicious versions

2 flagged

1.0.01.0.95530

Indicators of compromise (SHA-256)

b9407ceaf19f43da014ed05c29784c4732158aa6bcbfc0861a020e549d48dc99

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for biunfler (2 malicious versions).
If you installed it — respond
Remove biunfler 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 biunfler 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. biunfler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.95530 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07357

Credits

ReversingLabs · finder

Detect & block this

O3 blocks biunfler-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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