Which versions of besndler are malicious?

The following RubyGems versions of besndler are flagged malicious: 1.0.0, 1.0.70965. Treat any of these as compromised.

How do I remediate besndler if I installed it?

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

If besndler 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 besndler part of a known attack campaign?

Yes — besndler is associated with the RLMA-2026-07237 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 besndler across my projects, lockfiles, and CI pipelines?

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

Malicious package

besndlerRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

besndler is a confirmed malicious RubyGems package (MAL-2026-16582) that executes malicious code on install (malicious versions 1.0.0, 1.0.70965). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in besndler (RubyGems)

MAL-2026-16582

Immediate action

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

gem uninstall besndler

Malicious versions

2 flagged

1.0.01.0.70965

Indicators of compromise (SHA-256)

c876967dd46e6cdc960d7d6ba964b45e8ec0ba7e05cedaf7995ec2456a79f461

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for besndler (2 malicious versions).
If you installed it — respond
Remove besndler 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 besndler 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. besndler on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.70965 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07237

Credits

ReversingLabs · finder

Detect & block this

O3 blocks besndler-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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