Which versions of bunlderr are malicious?

The following RubyGems versions of bunlderr are flagged malicious: 1.0.6495. Treat any of these as compromised.

How do I remediate bunlderr if I installed it?

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

If bunlderr 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 bunlderr part of a known attack campaign?

Yes — bunlderr is associated with the RLMA-2026-07752 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 bunlderr across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for bunlderr (version 1.0.6495).

Malicious package

bunlderrRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bunlderr is a confirmed malicious RubyGems package (MAL-2026-17066) that executes malicious code on install (malicious version 1.0.6495). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bunlderr (RubyGems)

MAL-2026-17066

Immediate action

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

gem uninstall bunlderr

Malicious versions

1 flagged

1.0.6495

Indicators of compromise (SHA-256)

03f6cb52847c8b0049cdd6f060b73b1df3d325f1c10cb41c5228b5f827c51961

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bunlderr (version 1.0.6495).
If you installed it — respond
Remove bunlderr 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 bunlderr 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. bunlderr on RubyGems has been identified as a malicious package (version 1.0.6495 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07752

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bunlderr-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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