---
id: MAL-2026-16407
title: Malicious code in poly-check-b (PyPI)
summary: Malicious code in poly-check-b (PyPI)
severity: critical
exploited: true
vendor: poly-check-b
product: poly-check-b
ecosystem: pip
affected:
  - poly-check-b
published: '2026-09-22'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T19:00:03.995357241Z'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/MAL-2026-16407'
references:
  - url: 'https://bad-packages.kam193.eu/pypi/package/poly-check-b'
tags:
  - osv
  - pip
  - malware
ingestedAt: '2026-09-24T07:16:01.857Z'
---

## Overview


---
_-= Per source details. Do not edit below this line.=-_

## Source: kam193 (0e03276b0825e5aa683a1edd8c9a7f9947888cd03cde8c5351895a0fa3c2fba6)
During installation, the package attempts to silently execute code. In analyzed versions, the payload file was missing.


---

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


Campaign: 2026-09-snap-queue


Reasons (based on the campaign):


 - The package overrides the install command in setup.py to execute malicious code during installation.


## Affected packages

- `poly-check-b`

## Remediation

Refer to the advisory for the patched release.