Which versions of wtenc4 are malicious?

The following RubyGems versions of wtenc4 are flagged malicious: 0.0.1. Treat any of these as compromised.

How do I remediate wtenc4 if I installed it?

Remove wtenc4 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 wtenc4 — how do I know if it already compromised me?

If wtenc4 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 wtenc4 part of a known attack campaign?

Yes — wtenc4 is associated with the RLMA-2026-04139, RLUA-2026-10071 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 wtenc4 across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for wtenc4 (version 0.0.1).

Malicious package

wtenc4RubyGems

Advisory published Jul 7, 2026Updated Sep 24, 2026

wtenc4 is a confirmed malicious RubyGems package (MAL-2026-9488) that executes malicious code on install (malicious version 0.0.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in wtenc4 (RubyGems)

MAL-2026-9488

Immediate action

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

gem uninstall wtenc4

Malicious versions

1 flagged

0.0.1

Indicators of compromise (SHA-256)

c209b8cc5af91bf23fa61a5a8800166e442df3600f07fd1ee15be42c3e299b7e

9ece41b9c2153e490e9569782d556e486f9dc87d5926ab33218ab97e047be626

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for wtenc4 (version 0.0.1).
If you installed it — respond
Remove wtenc4 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 wtenc4 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. wtenc4 on RubyGems has been identified as a malicious package (version 0.0.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-04139RLUA-2026-10071

References

github.com

Credits

ReversingLabs · finder

Detect & block this

O3 blocks wtenc4-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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