Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, a ${...} expression or backtick in an enum default is emitted into a module-level template literal emitted by zod schema generation without safe encoding. This permits attacker-controlled JavaScript to be evaluated when the generated zod schema module is imported, resulting in code execution in the developer, CI, test, or application environment. The affected code is packages/zod/src/index.ts function formatDefaultValue. This issue is fixed in version 8.21.0.
Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, a ${...} expression or backtick in an enum default is emitted into a module-level template literal emitted by zod schema generation without safe encoding. This permits attacker-controlled JavaScript to be evaluated when the generated zod schema module is imported, resulting in code execution in the developer, CI, test, or application environment. The affected code is packages/zod/src/index.ts function formatDefaultValue. This issue is fixed in version 8.21.0.
Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, a ${...} expression or backtick in an enum default is emitted into a module-level template literal emitted by zod schema generation without safe encoding. This permits attacker-controlled JavaScript to be evaluated when the generated zod schema module is imported, resulting in code execution in the developer, CI, test, or application environment. The affected code is packages/zod/src/index.ts function formatDefaultValue. This issue is fixed in version 8.21.0.
### Summary
Orval's zod schema generation emits the **enum-typed** `default` value as a module-level template literal (`export const …Default = `<default>`;`) without escaping `${` or the backtick. A default of the form `v${<code>}w` injects a live JavaScript expression evaluated when the generated zod schema module is imported, executing attacker-controlled code at import — no request or function call needed. Verified on Orval 8.19.0; survives default OpenAPI validation.
### Details
```ts
export const …Default = `v${globalThis.ORVPWN()}w`; // ${...} = arbitrary JS expression, runs at import
```
Malicious input: an enum-typed property with a `default` of `v${<attacker JS>}w`. `${...}` permits any JS expression.
Note: this is one of several `default`-bearing positions that reach the same unescaped zod template-literal sink; a single fix (escape `default` values) closes all of them, and a CNA may choose to consolidate the related reports.
### PoC
`reproduce.sh` (+ `make_spec.py`) attached: generates the zod schema with default validation, bundles it, imports it, and shows a marker written at import. Verified on 8.19.0.
### Impact
Code execution at import in any application that imports a zod schema module generated from an attacker-controlled or attacker-influenced OpenAPI description.
### Suggested fix
Emit `default` values via a proper string-literal encoder (JSON.stringify, or escape backtick and `${` if a template literal must be used); never interpolate a spec value into a template literal. Apply to every `default` position.
EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.
Original publisher date fields
datePublished: Aug 19, 2026, 5:37:34 PM
dateUpdated: Aug 21, 2026, 7:43:39 PM
No normalized affected-package data is projected for this source revision. The original publisher record may contain additional product and version evidence; this does not establish that a package is unaffected.
NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.
Source analysis status: Deferred
Weakness classifications: CWE-94 · CWE-1336
Original publisher date fields
published: 2026-08-19T18:17:24.413
lastModified: 2026-09-09T21:20:38.860
No normalized affected-package data is projected for this source revision. The original publisher record may contain additional product and version evidence; this does not establish that a package is unaffected.