Which versions of zlibxjson are malicious?

The following PyPI versions of zlibxjson are flagged malicious: 8.1, 8.2. Treat any of these as compromised.

How do I remediate zlibxjson if I installed it?

zlibxjson is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.

I already installed zlibxjson — how do I know if it already compromised me?

If zlibxjson 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 zlibxjson part of a known attack campaign?

Yes — zlibxjson is associated with the RLMA-2024-09580, zlibxjson-discord-cookies, RLUA-2026-00950 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 zlibxjson across my projects, lockfiles, and CI pipelines?

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

Malicious package

zlibxjsonPyPI

Advisory published Jun 29, 2024Updated Mar 19, 2026

zlibxjson is a confirmed malicious PyPI package (MAL-2024-10220) that steals credentials and exfiltrates sensitive data (malicious versions 8.1, 8.2). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in zlibxjson (PyPI)

MAL-2024-10220

Immediate action

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

pip uninstall zlibxjson

What this malware does

Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.

Campaign: zlibxjson-discord-cookies

Reasons (based on the campaign):

infostealer

Malicious versions

2 flagged

8.18.2

Indicators of compromise (SHA-256)

83a74dd2a53c3a078e47bf329f0d116760cb1cce293fa36c4a9edf45c15b9138

51452ca037e090ebd2ac2ba19a0118cfe7a7b8a4f553c75df6193cb04dd2c3dc

7066166aef73a74278d8bf23450a89f6a42d22c8fac20660bc5275868b92d211

35640be665450143a4a26c497d0b25882befa96327f12e8758587ecf5f249bc7

3968164b2bc735ea7db194e0f59fe841b20831be557744f57fc4643141beec48

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for zlibxjson (2 malicious versions).
If you installed it — respond
zlibxjson is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If zlibxjson 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. zlibxjson on PyPI has been identified as a malicious package (versions 8.1, 8.2 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2024-09580zlibxjson-discord-cookiesRLUA-2026-00950

References

Credits

Kamil Mańkowski (kam193)
ReversingLabs · finder

Detect & block this

O3 blocks zlibxjson-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

Explore

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