Which versions of bumidler are malicious?

The following RubyGems versions of bumidler are flagged malicious: 1.0.0, 1.0.64617. Treat any of these as compromised.

How do I remediate bumidler if I installed it?

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

If bumidler 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 bumidler part of a known attack campaign?

Yes — bumidler is associated with the RLMA-2026-07567 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 bumidler across my projects, lockfiles, and CI pipelines?

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

Malicious package

bumidlerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bumidler is a confirmed malicious RubyGems package (MAL-2026-16881) that executes malicious code on install (malicious versions 1.0.0, 1.0.64617). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bumidler (RubyGems)

MAL-2026-16881

Immediate action

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

gem uninstall bumidler

Malicious versions

2 flagged

1.0.01.0.64617

Indicators of compromise (SHA-256)

04efaba7702fa5c0609c723dfd132d6d9a50397fafdfdf9497fac6253ac96390

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bumidler (2 malicious versions).
If you installed it — respond
Remove bumidler 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 bumidler 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. bumidler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.64617 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07567

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bumidler-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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