Vulnerability · Published Oct 2, 2026 · Assigned by GitHub_M
CVE-2026-104849Tinypool: Prototype Pollution Gadget to RCE in run() options
Critical 9.5
In plain English
A critical-severity code injection in tinypool from tinylibs. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | tinypool | 2.1.2 | GHSA-85c8-ppgw-ccpr |
Affected products (as reported)
Weakness: CWE-94, CWE-1321 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
References
- https://github.com/tinylibs/tinypool/security/advisories/GHSA-85c8-ppgw-ccpr x_refsource_CONFIRM
- https://github.com/tinylibs/tinypool/pull/135 x_refsource_MISC
- https://github.com/tinylibs/tinypool/commit/f41411a3e23324c674f35a19a3240f7a7c40ffbf x_refsource_MISC
- https://github.com/tinylibs/tinypool/releases/tag/v2.1.2 x_refsource_MISC