Which versions of bundaler are malicious?

The following RubyGems versions of bundaler are flagged malicious: 1.0.0, 1.0.97385. Treat any of these as compromised.

How do I remediate bundaler if I installed it?

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

If bundaler 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 bundaler part of a known attack campaign?

Yes — bundaler is associated with the RLMA-2026-07593 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 bundaler across my projects, lockfiles, and CI pipelines?

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

Malicious package

bundalerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bundaler is a confirmed malicious RubyGems package (MAL-2026-16907) that executes malicious code on install (malicious versions 1.0.0, 1.0.97385). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bundaler (RubyGems)

MAL-2026-16907

Immediate action

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

gem uninstall bundaler

Malicious versions

2 flagged

1.0.01.0.97385

Indicators of compromise (SHA-256)

23a440bca0f87d31dc5e2e6cf2560fab13f66dcd6b843cd6e7d8198cbd401406

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bundaler (2 malicious versions).
If you installed it — respond
Remove bundaler 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 bundaler 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. bundaler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.97385 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07593

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bundaler-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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