GHSA-x9g3-xrwr-cwfg · Severity: high · Ecosystem: npm — piscina: Prototype Pollution Gadget → RCE via inherited options.filename
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.
Conclusion & alert: CVE-2026-55388 is rated Low Risk (39.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.30%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-23 | — | 0.30% | — |
Full EPSS history (1 record total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.1 | 3.1 | HIGH |
|
2.2 | 5.9 | [email protected] |
GHSA-x9g3-xrwr-cwfg · Severity: high · Ecosystem: npm — piscina: Prototype Pollution Gadget → RCE via inherited options.filename
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| No affected products in dataset. | |||