Which versions of bumldler are malicious?

The following RubyGems versions of bumldler are flagged malicious: 1.0.0, 1.0.94213. Treat any of these as compromised.

How do I remediate bumldler if I installed it?

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

If bumldler 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 bumldler part of a known attack campaign?

Yes — bumldler is associated with the RLMA-2026-07570 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 bumldler across my projects, lockfiles, and CI pipelines?

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

Malicious package

bumldlerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bumldler is a confirmed malicious RubyGems package (MAL-2026-16884) that executes malicious code on install (malicious versions 1.0.0, 1.0.94213). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bumldler (RubyGems)

MAL-2026-16884

Immediate action

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

gem uninstall bumldler

Malicious versions

2 flagged

1.0.01.0.94213

Indicators of compromise (SHA-256)

7799247763c57aa0690fb5d70a9a0da6a84ef48d45ec9b035858681d40fe2dd1

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bumldler (2 malicious versions).
If you installed it — respond
Remove bumldler 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 bumldler 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. bumldler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.94213 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07570

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bumldler-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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