Which versions of bumder are malicious?

The following RubyGems versions of bumder are flagged malicious: 1.0.0, 1.0.19715. Treat any of these as compromised.

How do I remediate bumder if I installed it?

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

If bumder 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 bumder part of a known attack campaign?

Yes — bumder is associated with the RLMA-2026-07507 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 bumder across my projects, lockfiles, and CI pipelines?

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

Malicious package

bumderRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bumder is a confirmed malicious RubyGems package (MAL-2026-16821) that executes malicious code on install (malicious versions 1.0.0, 1.0.19715). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bumder (RubyGems)

MAL-2026-16821

Immediate action

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

gem uninstall bumder

Malicious versions

2 flagged

1.0.01.0.19715

Indicators of compromise (SHA-256)

d9eec7e1c99f9c5225f84e8ea3ab66c614f196880f206073d16b7e8dd04a66a8

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bumder (2 malicious versions).
If you installed it — respond
Remove bumder 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 bumder 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. bumder on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.19715 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07507

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bumder-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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