---
id: "MAL-2026-16407"
kind: "package"
aliases: ["MAL-2026-16407"]
title: "Malicious code in poly-check-b (PyPI)"
severity: "critical"
cvss: null
epss: null
exploited: false
status: "open"
category: "package"
products: [{"name": "poly-check-b", "fixed": [], "affected": "= 1.0.0", "ecosystem": "pypi"}]
ecosystems: ["pypi"]
tags: ["malicious", "package"]
not_affected_if: []
published_at: "2026-09-22T18:41:04+00:00"
first_seen_at: "2026-10-26T20:51:57+00:00"
updated_at: "2026-10-26T21:10:31+00:00"
sources: [{"source": "osv-malicious", "url": "https://osv.dev/vulnerability/MAL-2026-16407", "first_seen_at": "2026-10-26T20:51:57+00:00"}]
---

# Malicious code in poly-check-b (PyPI)

## Affected

- pypi:poly-check-b affected = 1.0.0 fixed ?

## Timeline

- 2026-10-26T20:51:57+00:00 osv-malicious https://osv.dev/vulnerability/MAL-2026-16407

## From the sources

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_-= 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.

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