What’s Vulnerable › Vulnerabilities

CVE-2026-104849: Tinypool: Prototype Pollution Gadget to RCE in run() options

• Severity: critical (CVSS 9.5 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-02 · updated 2026-10-06
• Weakness: CWE-94

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 products

• tinylibs tinypool: before 2.1.2

References

• https://github.com/tinylibs/tinypool/commit/f41411a3e23324c674f35a19a3240f7a7c40ffbf
• https://github.com/tinylibs/tinypool/pull/135
• https://github.com/tinylibs/tinypool/releases/tag/v2.1.2
• https://github.com/tinylibs/tinypool/security/advisories/GHSA-85c8-ppgw-ccpr
• https://github.com/tinylibs/tinypool/security/advisories/GHSA-85c8-ppgw-ccpr

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