Medium severity · published Oct 2, 2026
CVE-2026-103918
@orpc/zod: Prototype injection in smart coercion
6.5
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OR
orpc · middleapi
< 1.14.10 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-103918
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-103918
x_refsource_CONFIRM
https://github.com/middleapi/orpc/security/advisories/GHSA-gcgf-fh7c-8gf2
x_refsource_MISC
https://github.com/middleapi/orpc/pull/1727
x_refsource_MISC
https://github.com/middleapi/orpc/commit/26314dfb443237c495116c5794d3d30a7a22c570
x_refsource_MISC
https://github.com/middleapi/orpc/releases/tag/v1.14.10
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