---
id: "MAL-2026-18451"
kind: "package"
aliases: ["MAL-2026-18451"]
title: "Malicious code in contracts-upgradeable (npm)"
severity: "critical"
cvss: null
epss: null
exploited: false
status: "open"
category: "package"
products: [{"name": "contracts-upgradeable", "fixed": [], "affected": "= 1.0.0", "ecosystem": "npm"}]
ecosystems: ["npm"]
tags: ["malicious", "package"]
not_affected_if: []
published_at: "2026-11-02T02:31:07+00:00"
first_seen_at: "2026-11-02T06:51:32+00:00"
updated_at: "2026-11-02T06:53:35+00:00"
sources: [{"source": "osv-malicious", "url": "https://osv.dev/vulnerability/MAL-2026-18451", "first_seen_at": "2026-11-02T06:51:32+00:00"}]
---

# Malicious code in contracts-upgradeable (npm)

## Affected

- npm:contracts-upgradeable affected = 1.0.0 fixed ?

## Timeline

- 2026-11-02T06:51:32+00:00 osv-malicious https://osv.dev/vulnerability/MAL-2026-18451

## From the sources

contracts-upgradeable takes the unscoped name of @openzeppelin/contracts-upgradeable and has no functional code. Its preinstall script runs `node preinstall.js` on npm install, which POSTs the machine's hostname, the OS username and the local time to the Discord webhook `https://canary.discord.com/api/webhooks/1566232728179843243/pM5rDIrCRrEpQRbA7ibaiQk1XOQlIftmBacA5s8jD8NvXn5W-rS832DOWHQS-G-j3N6U` as "PC Notifier". It was published on 2026-11-02 by the npm account bigdevin55, which published sol-wallet-adapter 1.0.7 with the same script the same day; the account cutekitten05 used the same webhook in packages published on 2026-11-01.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_