Which versions of bundloer are malicious?

The following RubyGems versions of bundloer are flagged malicious: 1.0.0, 1.0.91886. Treat any of these as compromised.

How do I remediate bundloer if I installed it?

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

If bundloer 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 bundloer part of a known attack campaign?

Yes — bundloer is associated with the RLMA-2026-07677 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 bundloer across my projects, lockfiles, and CI pipelines?

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

Malicious package

bundloerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bundloer is a confirmed malicious RubyGems package (MAL-2026-16991) that executes malicious code on install (malicious versions 1.0.0, 1.0.91886). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bundloer (RubyGems)

MAL-2026-16991

Immediate action

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

gem uninstall bundloer

Malicious versions

2 flagged

1.0.01.0.91886

Indicators of compromise (SHA-256)

5579deea07d0bd106377afce47c57405b6c31d8fd21ad9286c6da09497774911

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bundloer (2 malicious versions).
If you installed it — respond
Remove bundloer 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 bundloer 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. bundloer on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.91886 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07677

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bundloer-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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