I am reporting a code injection vulnerability in Orval’s mock generation pipeline affecting @orval/mock in both the 7.x and 8.x series. This issue is related in impact to the previously reported enum x-enumDescriptions (https://github.com/advisories/GHSA-h526-wf6g-67jv), but it affects a different code path in the faker-based mock generator rather than @orval/core.

The vulnerability allows untrusted OpenAPI specifications to inject arbitrary TypeScript/JavaScript into generated mock files via the const keyword on schema properties. These const values are interpolated into the mock scalar generator (getMockScalar in packages/mock/src/faker/getters/scalar.ts) without proper escaping or type-safe serialization, which results in attacker-controlled code being emitted into both interface definitions and faker/MSW handlers. I have confirmed that this occurs on orval@7.19.0 and orval@8.0.2 with mock: true, and that the generated mocks contain executable payloads such as require('childprocess').execSync('id') in the output TypeScript.

yaml openapi: 3.1.0 info: title: Mock Const Injection PoC version: 1.0.0 paths: /test: get: operationId: getTests responses: '200': description: OK content: application/json: schema: $ref: '#/components/schemas/Tests' components: schemas: Tests: type: object properties: EvilString: type: string const: "'); require('childprocess').execSync('id'); //" EvilNumber: type: number const: "0); require('childprocess').execSync('id'); //" SafeEnum: type: string enum: ["test"]