CVE-2026-104849

Tinypool is a minimal Node.js worker thread pool implementation. Prior to 2.1.2, Tinypool reads filename from a caller-supplied options object in pool.run(task, options) without requiring an own property, so a polluted Object.prototype.filename can replace the intended worker module. Applications are affected only when they pass their own second-argument options object to pool.run(); calls without that argument use the trusted default options object. An attacker who can first pollute the prototype can cause the worker pool to load attacker-selected JavaScript and can read or modify task data with the host process's privileges. This issue is fixed in version 2.1.2.

  • Published Oct 2, 2026
  • CVSS 9.5 critical
  • 0.4% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-104849 at the National Vulnerability Database