CVE-2026-55388
piscina: Prototype Pollution Gadget → RCE via inherited options.filename
HIGH 8.1EPSS 0.5%
piscina is a node.js worker pool implementation. Prior to 6.0.0-rc.2, 5.2.0, and 4.9.3, piscina's constructor and run() paths read the filename option via plain member access. Both reads fall through the prototype chain when the caller's options object doesn't have filename as an own property. When Object.prototype.filename is polluted upstream the inherited value flows to worker_threads.Worker import and the attacker's .mjs runs in the worker. This vulnerability is fixed in 6.0.0-rc.2, 5.2.0, and 4.9.3.
- Affected
- piscinajs · piscina
- CVSS v3.1 GITHUB
- 8.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS
- 0.45% chance of exploitation in the next 30 days, 38th percentile
- Published
- 2026-06-22
- Updated
- 2026-06-23