Which versions of bundlsef are malicious?

The following RubyGems versions of bundlsef are flagged malicious: 1.0.0, 1.0.8469. Treat any of these as compromised.

How do I remediate bundlsef if I installed it?

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

If bundlsef 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 bundlsef part of a known attack campaign?

Yes — bundlsef is associated with the RLMA-2026-07685 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 bundlsef across my projects, lockfiles, and CI pipelines?

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

Malicious package

bundlsefRubyGems

Advisory published Sep 22, 2026Updated Sep 24, 2026

bundlsef is a confirmed malicious RubyGems package (MAL-2026-16999) that executes malicious code on install (malicious versions 1.0.0, 1.0.8469). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bundlsef (RubyGems)

MAL-2026-16999

Immediate action

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

gem uninstall bundlsef

Malicious versions

2 flagged

1.0.01.0.8469

Indicators of compromise (SHA-256)

eb9a0c15210f80d294c782b1b1b12b4a9393163359b698bada2347c07a796248

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for bundlsef (2 malicious versions).
If you installed it — respond
Remove bundlsef 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 bundlsef 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. bundlsef on RubyGems has been identified as a malicious package (versions 1.0.0, 1.0.8469 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-07685

Credits

ReversingLabs · finder

Detect & block this

O3 blocks bundlsef-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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