CVE-2026-103036

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/middleapi/orpc/commit/8a352622e756e8956311f5836cd5c5b9219c0666
https://github.com/middleapi/orpc/pull/1726
https://github.com/middleapi/orpc/releases/tag/v1.14.9
https://github.com/middleapi/orpc/security/advisories/GHSA-4h5r-cv8j-4456

Configurations

No configuration.

History

02 Oct 2026, 20:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-02 20:16

Updated : 2026-10-06 15:18

NVD link : CVE-2026-103036

Mitre link : CVE-2026-103036

CVE.ORG link : CVE-2026-103036

JSON object : View

Products Affected

No product.

CWE

CWE-915

Improperly Controlled Modification of Dynamically-Determined Object Attributes

CWE-1321

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

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