Which versions of wcaldt are malicious?

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

How do I remediate wcaldt if I installed it?

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

If wcaldt 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 wcaldt part of a known attack campaign?

Yes — wcaldt is associated with the RLMA-2026-03972, RLUA-2026-09902 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 wcaldt across my projects, lockfiles, and CI pipelines?

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

Malicious package

wcaldtRubyGems

Advisory published Jul 7, 2026Updated Sep 24, 2026

wcaldt is a confirmed malicious RubyGems package (MAL-2026-9321) 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 wcaldt (RubyGems)

MAL-2026-9321

Immediate action

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

gem uninstall wcaldt

Malicious versions

1 flagged

0.0.1

Indicators of compromise (SHA-256)

4b20aea92bb33a8264bee4cd24c56b91229c63ecae6195175615a4663bd2b135

e40b9ec450ca9ca57bb5ccb72343c5a902c13f93391660f3dbd4978dae6f721e

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for wcaldt (version 0.0.1).
If you installed it — respond
Remove wcaldt 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 wcaldt 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. wcaldt 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-2026-03972RLUA-2026-09902

References

github.com

Credits

ReversingLabs · finder

Detect & block this

O3 blocks wcaldt-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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