oRPC is a tool that helps build APIs that are end-to-end type-safe and adhere to OpenAPI standards. Prior to 1.14.9, the @orpc/json-schema SmartCoercionPlugin uses JsonSchemaCoercer to collect object properties in a plain object and to resolve schema.properties entries through the prototype chain. A remote client that can reach a procedure with an object input schema can supply __proto__ to replace the prototype of the single coerced request object, or supply Object.prototype member names such as constructor and toString so inherited values are treated as sub-schemas and pass the coercer's satisfaction check. Attacker-controlled inherited properties can consequently affect handler, Object.assign, or configuration lookups, while legitimate __proto__ properties are dropped. The global Object.prototype, unrelated objects, other requests, and other users are not modified, and downstream schema validation still runs. This issue is fixed in version 1.14.9.

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Fri, 02 Oct 2026 22:15:00 +0000

Type Values Removed Values Added
First Time appeared Middleapi
Middleapi orpc
Vendors & Products Middleapi
Middleapi orpc

Fri, 02 Oct 2026 20:15:00 +0000

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Description oRPC is a tool that helps build APIs that are end-to-end type-safe and adhere to OpenAPI standards. Prior to 1.14.9, the @orpc/json-schema SmartCoercionPlugin uses JsonSchemaCoercer to collect object properties in a plain object and to resolve schema.properties entries through the prototype chain. A remote client that can reach a procedure with an object input schema can supply __proto__ to replace the prototype of the single coerced request object, or supply Object.prototype member names such as constructor and toString so inherited values are treated as sub-schemas and pass the coercer's satisfaction check. Attacker-controlled inherited properties can consequently affect handler, Object.assign, or configuration lookups, while legitimate __proto__ properties are dropped. The global Object.prototype, unrelated objects, other requests, and other users are not modified, and downstream schema validation still runs. This issue is fixed in version 1.14.9.
Title @orpc/json-schema: Prototype injection in smart coercion
Weaknesses CWE-1321
CWE-915
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-10-02T20:00:46.620Z

Reserved: 2026-09-29T21:13:24.032Z

Link: CVE-2026-103036

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-02T20:16:59.567

Modified: 2026-10-02T20:16:59.567

Link: CVE-2026-103036

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-02T22:00:24Z

Weaknesses