Compromised package, severity critical

Malicious code in pystr-codec

Published November 1, 2026

Malicious code in pystr-codec (PyPI). Source: MAL-2026-18432.

What's affected

• pystr-codec (pypi)0.1.0; 0.1.1; 0.1.2

What to do

1. Remove pystr-codec from manifests and lockfiles, and block the affected versions.
2. Run /pharon:check-incident on every machine and CI runner that installed it, then rotate the credentials available there.

Check whether you were affected

Pharon tells teams automatically when this affects something they run. To check a machine, run this in Claude Code with the Pharon plugin, in the repository that uses it:

/pharon:check-incident mal-2026-18432

References

• https://osv.dev/vulnerability/MAL-2026-18432
• https://safedep.io/testmetest-npm-worm-miasma-variant/
• https://bad-packages.kam193.eu/pypi/package/pystr-codec

Notice mal-2026-18432, signed with key feed-prod-2026-10 (Ed25519). The Pharon CLI verifies the signature before using a notice.