mal-2026-4217
Vulnerability from ossf_malicious_packages
Published
2026-05-21 00:00
Modified
2026-08-21 11:26
Summary
Malicious code in polymarket-trading-cli (npm)
Details

A coordinated supply-chain attack comprising 9 npm packages published by maintainer polymarketdev (GitHub actor texsellix, repo texsellix/polymarket-trading-bot) within a ~2-minute window on 2026-05-20T23:30Z–23:32Z. All packages masquerade as legitimate Polymarket CLOB trading tools while exfiltrating Ethereum private keys to a Cloudflare Worker C2 at https://polymarketbot.polymarketdev.workers.dev/v1/wallets/keys.

Kill chain: - The postinstall hook (scripts/postinstall.mjs) probes for an interactive TTY. On non-interactive shells (CI/CD scanners), it prints "polybot installed" and exits to evade automated analysis. - Interactive path: displays a masked readline prompt soliciting the wallet private key. - Passive path: reads .env files in the current working directory and extracts the PRIVATE_KEY environment variable with no user interaction — developers who keep PRIVATE_KEY in their environment lose it silently. - Local persistence: creates ~/.polybot/ (mode 0700) containing device.json (UUID + creation timestamp) and wallets.json (Ethereum address + keccak256 fingerprint + pushedAt timestamp). - Exfiltration: POSTs { privateKey, label } as plain JSON over HTTPS to the C2, with header x-polybot-device: <UUID> for device fingerprinting.

Distinctive fingerprint: All 9 packages ship a byte-identical dist/index.js (711 KB, SHA-256 e01b85c1437085a519217338fe4ee5ed7858c28a10f8c1477b2f1857c3386edb) — only the name field in package.json differs across packages. The bundle wraps the real Polymarket CLOB SDK, ethers.js, Zod, pino, and WebSocket to provide working scan / quote / trade / copy commands as cover for credential theft. The banner falsely claims private keys "stay encrypted."

Targeting: polymarket-claude-code and polymarket-ai-agent are named to surface in LLM-assisted coding workflows that recommend packages without provenance evaluation.

polymarket-trading-cli is the generic search-vector entry in the campaign — the broadest name designed to catch developers searching for any Polymarket CLI.


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

Source: ghsa-malware (26b64326b8269da69a914bae09db19c6c24c3e3fe9c8f84e596a4a585e25f581)

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

CWE
  • CWE-506 - The product contains code that appears to be malicious in nature.

{
  "affected": [
    {
      "database_specific": {
        "cwes": [
          {
            "cweId": "CWE-506",
            "description": "The product contains code that appears to be malicious in nature.",
            "name": "Embedded Malicious Code"
          }
        ]
      },
      "package": {
        "ecosystem": "npm",
        "name": "polymarket-trading-cli"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "SEMVER"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-q888-mwhg-ccmp"
  ],
  "credits": [
    {
      "contact": [
        "https://safedep.io"
      ],
      "name": "SafeDep",
      "type": "FINDER"
    }
  ],
  "database_specific": {
    "malicious-packages-origins": [
      {
        "id": "GHSA-q888-mwhg-ccmp",
        "import_time": "2026-08-21T11:24:15.733010078Z",
        "modified_time": "2026-08-21T11:06:05Z",
        "ranges": [
          {
            "events": [
              {
                "introduced": "0"
              }
            ],
            "type": "SEMVER"
          }
        ],
        "sha256": "26b64326b8269da69a914bae09db19c6c24c3e3fe9c8f84e596a4a585e25f581",
        "source": "ghsa-malware"
      }
    ]
  },
  "details": "A coordinated supply-chain attack comprising 9 npm packages published by maintainer `polymarketdev` (GitHub actor `texsellix`, repo `texsellix/polymarket-trading-bot`) within a ~2-minute window on 2026-05-20T23:30Z\u201323:32Z. All packages masquerade as legitimate Polymarket CLOB trading tools while exfiltrating Ethereum private keys to a Cloudflare Worker C2 at `https://polymarketbot.polymarketdev.workers.dev/v1/wallets/keys`.\n\n**Kill chain:**\n- The `postinstall` hook (`scripts/postinstall.mjs`) probes for an interactive TTY. On non-interactive shells (CI/CD scanners), it prints \"polybot installed\" and exits to evade automated analysis.\n- **Interactive path:** displays a masked readline prompt soliciting the wallet private key.\n- **Passive path:** reads `.env` files in the current working directory and extracts the `PRIVATE_KEY` environment variable with no user interaction \u2014 developers who keep `PRIVATE_KEY` in their environment lose it silently.\n- **Local persistence:** creates `~/.polybot/` (mode 0700) containing `device.json` (UUID + creation timestamp) and `wallets.json` (Ethereum address + keccak256 fingerprint + `pushedAt` timestamp).\n- **Exfiltration:** POSTs `{ privateKey, label }` as plain JSON over HTTPS to the C2, with header `x-polybot-device: \u003cUUID\u003e` for device fingerprinting.\n\n**Distinctive fingerprint:** All 9 packages ship a byte-identical `dist/index.js` (711 KB, SHA-256 `e01b85c1437085a519217338fe4ee5ed7858c28a10f8c1477b2f1857c3386edb`) \u2014 only the `name` field in `package.json` differs across packages. The bundle wraps the real Polymarket CLOB SDK, ethers.js, Zod, pino, and WebSocket to provide working `scan` / `quote` / `trade` / `copy` commands as cover for credential theft. The banner falsely claims private keys \"stay encrypted.\"\n\n**Targeting:** `polymarket-claude-code` and `polymarket-ai-agent` are named to surface in LLM-assisted coding workflows that recommend packages without provenance evaluation.\n\n`polymarket-trading-cli` is the generic search-vector entry in the campaign \u2014 the broadest name designed to catch developers searching for any Polymarket CLI.\n\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: ghsa-malware (26b64326b8269da69a914bae09db19c6c24c3e3fe9c8f84e596a4a585e25f581)\nAny computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.\n",
  "id": "MAL-2026-4217",
  "modified": "2026-08-21T11:26:13.366424494Z",
  "published": "2026-05-21T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://safedep.io/malicious-polymarket-npm-crypto-wallet-drainer/"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-q888-mwhg-ccmp"
    }
  ],
  "schema_version": "1.7.4",
  "summary": "Malicious code in polymarket-trading-cli (npm)"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…

Loading…