Which versions of zwcalx4 are malicious?

The following RubyGems versions of zwcalx4 are flagged malicious: 0.0.488. Treat any of these as compromised.

How do I remediate zwcalx4 if I installed it?

Remove zwcalx4 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 zwcalx4 — how do I know if it already compromised me?

If zwcalx4 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 zwcalx4 part of a known attack campaign?

Yes — zwcalx4 is associated with the RLMA-2026-04498, RLUA-2026-10436 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 zwcalx4 across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for zwcalx4 (version 0.0.488).

Malicious package

zwcalx4RubyGems

Advisory published Jul 7, 2026Updated Sep 24, 2026

zwcalx4 is a confirmed malicious RubyGems package (MAL-2026-9847) that executes malicious code on install (malicious version 0.0.488). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in zwcalx4 (RubyGems)

MAL-2026-9847

Immediate action

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

gem uninstall zwcalx4

Malicious versions

1 flagged

0.0.488

Indicators of compromise (SHA-256)

26a1f956893120af9d9c94f14d6a1a84504269de3b17b8f5781d0d6c8dcc1208

842fb0c6d9c5ef31b42aabab05e1506e6518058a84ae1e6f2ae3234a125e6b28

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for zwcalx4 (version 0.0.488).
If you installed it — respond
Remove zwcalx4 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 zwcalx4 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. zwcalx4 on RubyGems has been identified as a malicious package (version 0.0.488 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-04498RLUA-2026-10436

References

Credits

ReversingLabs · finder

Detect & block this

O3 blocks zwcalx4-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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