Which versions of jsonist are malicious?

The following PyPI versions of jsonist are flagged malicious: 0.1.0. Treat any of these as compromised.

How do I remediate jsonist if I installed it?

jsonist 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 jsonist — how do I know if it already compromised me?

If jsonist was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.

Is jsonist part of a known attack campaign?

Yes — jsonist is associated with the 2025-08-secmeasure 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 jsonist across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for jsonist (version 0.1.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging jsonist across your stack and pipelines.

Malicious package

jsonistPyPI

Malicious code in jsonist (PyPI) Remove it immediately and rotate any exposed credentials.

MAL-2025-191767

Immediate action

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

pip uninstall jsonist

What this malware does

Calling a method starts downloading and starting an infostealer script

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

Campaign: 2025-08-secmeasure

Reasons (based on the campaign):

action-hidden-in-lib-usage
Downloads and executes a remote malicious script.
infostealer

Malicious versions

1 flagged

0.1.0

Indicators of compromise (SHA-256)

7f3396007d526f88250ad2b5c324ad8a550418f97213066b820b379ebd2cdbe6

4c74a199a696dbc18994242bc3c29e9a018ddda51fa2bbe224620d9ded6f1818

Detection & response playbook

Credential / info stealer

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for jsonist (version 0.1.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging jsonist across your stack and pipelines.
If you installed it — respond
jsonist 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 jsonist was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks jsonist before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.

Frequently asked questions

No. jsonist on PyPI has been identified as a malicious package (version 0.1.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

2025-08-secmeasure

References

bad-packages.kam193.eu

Credits

Kamil Mańkowski (kam193)

Detect & block this

O3 blocks jsonist-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