CVE-2026-55388

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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/piscinajs/piscina/security/advisories/GHSA-x9g3-xrwr-cwfg
https://github.com/piscinajs/piscina/security/advisories/GHSA-x9g3-xrwr-cwfg

Configurations

No configuration.

History

23 Jun 2026, 17:17

Type	Values Removed	Values Added
References	~~() https://github.com/piscinajs/piscina/security/advisories/GHSA-x9g3-xrwr-cwfg -~~	() https://github.com/piscinajs/piscina/security/advisories/GHSA-x9g3-xrwr-cwfg -

22 Jun 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-22 18:16

Updated : 2026-06-23 17:17

NVD link : CVE-2026-55388

Mitre link : CVE-2026-55388

CVE.ORG link : CVE-2026-55388

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

CWE-1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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