Which versions of parsimonius are malicious?

The following PyPI versions of parsimonius are flagged malicious: 0.10.0, 0.11.0, 0.11.1, 0.11.2, 0.11.3, 0.11.4, 0.11.5, 0.11.6, 0.12.0. Treat any of these as compromised.

How do I remediate parsimonius if I installed it?

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

If parsimonius 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 parsimonius part of a known attack campaign?

Yes — parsimonius is associated with the 2026-06-parsimonius 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 parsimonius 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 parsimonius (9 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging parsimonius across your stack and pipelines.

Malicious package

parsimoniusPyPI

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

MAL-2026-5151

Immediate action

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

pip uninstall parsimonius

What this malware does

Clone of a legitimate package with an added RAT running through a Telegram bot. It can e.g. exfiltrate env variables and execute remote commands. The malicious action does not start if the geolocation or timezone suggests a Russian area.

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

Campaign: 2026-06-parsimonius

Reasons (based on the campaign):

typosquatting
exfiltration-env-variables
The package contains code to execute remote commands (probably limited to a specific set) on the victim's machine.
rat
clones-real-package
abuses-pth
geo-restricted
uses-telegram-bot

Malicious versions

9 flagged

0.10.00.11.00.11.10.11.20.11.30.11.40.11.50.11.60.12.0

Indicators of compromise (SHA-256)

a5ab85a46a37da928774b1885049b71d40d675c54683b13711f4e371d932394a

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 parsimonius (9 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging parsimonius across your stack and pipelines.
If you installed it — respond
parsimonius 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 parsimonius 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 parsimonius 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. parsimonius on PyPI has been identified as a malicious package (versions 0.10.0, 0.11.0, 0.11.1, 0.11.2, 0.11.3, 0.11.4, 0.11.5, 0.11.6, and 1 more flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

2026-06-parsimonius

References

bad-packages.kam193.eu

Credits

Kamil Mańkowski (kam193) · reporter

Detect & block this

O3 blocks parsimonius-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