Which versions of bumadler are malicious?

The following RubyGems versions of bumadler are flagged malicious: 1.0.0, 1.0.74956. Treat any of these as compromised.

How do I remediate bumadler if I installed it?

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

If bumadler 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 bumadler part of a known attack campaign?

Yes — bumadler is associated with the RLMA-2026-07498 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 bumadler across my projects, lockfiles, and CI pipelines?

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

Malicious package

bumadlerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bumadler is a confirmed malicious RubyGems package (MAL-2026-16812) that executes malicious code on install (malicious versions 1.0.0, 1.0.74956). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bumadler (RubyGems)

MAL-2026-16812

Immediate action

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

gem uninstall bumadler

Malicious versions

2 flagged

1.0.01.0.74956

Indicators of compromise (SHA-256)

6ec9964de1f71a11aa7e9d7bb762ba5d32fc9c7e4877275bb5b57405da4e3009

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bumadler (2 malicious versions).
If you installed it — respond
Remove bumadler 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 bumadler 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. bumadler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.74956 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07498

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bumadler-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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