Which versions of buncler are malicious?

The following RubyGems versions of buncler are flagged malicious: 1.0.0, 1.0.33420. Treat any of these as compromised.

How do I remediate buncler if I installed it?

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

If buncler 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 buncler part of a known attack campaign?

Yes — buncler is associated with the RLMA-2026-07589 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 buncler across my projects, lockfiles, and CI pipelines?

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

Malicious package

bunclerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

buncler is a confirmed malicious RubyGems package (MAL-2026-16903) that executes malicious code on install (malicious versions 1.0.0, 1.0.33420). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in buncler (RubyGems)

MAL-2026-16903

Immediate action

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

gem uninstall buncler

Malicious versions

2 flagged

1.0.01.0.33420

Indicators of compromise (SHA-256)

c9a30ad11a09b11ac4c1de3890b7f2647fd5558a7b9b96b81e6e33deb5198cde

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for buncler (2 malicious versions).
If you installed it — respond
Remove buncler 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 buncler 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. buncler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.33420 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07589

Credits

ReversingLabs · finder

Detect & block this

O3 blocks buncler-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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