Which versions of zwcalx13 are malicious?

The following RubyGems versions of zwcalx13 are flagged malicious: 0.0.499. Treat any of these as compromised.

How do I remediate zwcalx13 if I installed it?

Remove zwcalx13 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 zwcalx13 — how do I know if it already compromised me?

If zwcalx13 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 zwcalx13 part of a known attack campaign?

Yes — zwcalx13 is associated with the RLMA-2026-04495, RLUA-2026-10433 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 zwcalx13 across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for zwcalx13 (version 0.0.499).

Malicious package

zwcalx13RubyGems

Advisory published Jul 7, 2026Updated Sep 24, 2026

zwcalx13 is a confirmed malicious RubyGems package (MAL-2026-9844) that executes malicious code on install (malicious version 0.0.499). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in zwcalx13 (RubyGems)

MAL-2026-9844

Immediate action

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

gem uninstall zwcalx13

Malicious versions

1 flagged

0.0.499

Indicators of compromise (SHA-256)

36af82b7a0abb43007c467ccf8fa81e97c8180d8135603908944c82b5665cc3f

6ddbd05371824e5287d35fd6f7b747b2675454d98ab44cf91aade6b2048e42f4

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for zwcalx13 (version 0.0.499).
If you installed it — respond
Remove zwcalx13 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 zwcalx13 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. zwcalx13 on RubyGems has been identified as a malicious package (version 0.0.499 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-04495RLUA-2026-10433

References

Credits

ReversingLabs · finder

Detect & block this

O3 blocks zwcalx13-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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