Which versions of bunldr are malicious?

The following RubyGems versions of bunldr are flagged malicious: 1.0.15959. Treat any of these as compromised.

How do I remediate bunldr if I installed it?

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

If bunldr 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 bunldr part of a known attack campaign?

Yes — bunldr is associated with the RLMA-2026-07763 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 bunldr across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for bunldr (version 1.0.15959).

Malicious package

bunldrRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bunldr is a confirmed malicious RubyGems package (MAL-2026-17077) that executes malicious code on install (malicious version 1.0.15959). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bunldr (RubyGems)

MAL-2026-17077

Immediate action

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

gem uninstall bunldr

Malicious versions

1 flagged

1.0.15959

Indicators of compromise (SHA-256)

30fd6bf5a9134cedbc4cbe721dff0621743b7bf2f39dc1e84493270ea513ee6c

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bunldr (version 1.0.15959).
If you installed it — respond
Remove bunldr 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 bunldr 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. bunldr on RubyGems has been identified as a malicious package (version 1.0.15959 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07763

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bunldr-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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