CVE-2026-103918
@orpc/zod: Prototype injection in smart coercion
Description
oRPC is a tool that helps build APIs that are end-to-end type-safe and adhere to OpenAPI standards. Prior to 1.14.10, the @orpc/zod ZodSmartCoercionPlugin and experimental_ZodSmartCoercionPlugin collect object and record properties in plain objects and resolve shape keys through the prototype chain. A remote client that can reach a procedure with an object or record input can supply __proto__ to replace the prototype of the returned request object, allowing attacker-controlled inherited values to reach application lookups. For object schemas, keys such as constructor, toString, and __proto__ can instead resolve inherited members as Zod schemas and cause an unhandled TypeError before validation. The global Object.prototype, unrelated objects, other requests, and other users are not modified, and the availability effect is limited to crafted requests rather than persistent process-wide state. This issue is fixed in version 1.14.10.
INFO
Published Date :
Oct. 2, 2026, 8:17 p.m.
Last Modified :
Oct. 2, 2026, 8:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update the oRPC package to 1.14.10 or later.
- Apply security patches for the ZodSmartCoercionPlugin.
- Review input validation for object and record types.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-103918.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-103918 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-103918
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2026-103918 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-103918 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
Oct. 02, 2026
Action Type Old Value New Value Added Description oRPC is a tool that helps build APIs that are end-to-end type-safe and adhere to OpenAPI standards. Prior to 1.14.10, the @orpc/zod ZodSmartCoercionPlugin and experimental_ZodSmartCoercionPlugin collect object and record properties in plain objects and resolve shape keys through the prototype chain. A remote client that can reach a procedure with an object or record input can supply __proto__ to replace the prototype of the returned request object, allowing attacker-controlled inherited values to reach application lookups. For object schemas, keys such as constructor, toString, and __proto__ can instead resolve inherited members as Zod schemas and cause an unhandled TypeError before validation. The global Object.prototype, unrelated objects, other requests, and other users are not modified, and the availability effect is limited to crafted requests rather than persistent process-wide state. This issue is fixed in version 1.14.10. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N Added CWE CWE-915 Added CWE CWE-1321 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/103xxx/CVE-2026-103918.json">CVE-2026-103918</a> Added Reference https://github.com/middleapi/orpc/commit/26314dfb443237c495116c5794d3d30a7a22c570 Added Reference https://github.com/middleapi/orpc/pull/1727 Added Reference https://github.com/middleapi/orpc/releases/tag/v1.14.10 Added Reference https://github.com/middleapi/orpc/security/advisories/GHSA-gcgf-fh7c-8gf2