Which versions of bunlder-gem are malicious?

The following RubyGems versions of bunlder-gem are flagged malicious: 1.0.50306. Treat any of these as compromised.

How do I remediate bunlder-gem if I installed it?

Remove bunlder-gem 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 bunlder-gem — how do I know if it already compromised me?

If bunlder-gem 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 bunlder-gem part of a known attack campaign?

Yes — bunlder-gem is associated with the RLMA-2026-07742 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 bunlder-gem across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for bunlder-gem (version 1.0.50306).

Malicious package

bunlder-gemRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bunlder-gem is a confirmed malicious RubyGems package (MAL-2026-17056) that executes malicious code on install (malicious version 1.0.50306). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bunlder-gem (RubyGems)

MAL-2026-17056

Immediate action

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

gem uninstall bunlder-gem

Malicious versions

1 flagged

1.0.50306

Indicators of compromise (SHA-256)

ffacf144ba76c5e73ef9635e47df5faf1a76050ce6a5d69cb538a8363d6966e2

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bunlder-gem (version 1.0.50306).
If you installed it — respond
Remove bunlder-gem 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 bunlder-gem 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. bunlder-gem on RubyGems has been identified as a malicious package (version 1.0.50306 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07742

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bunlder-gem-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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