GHSA-38c3-wv3c-v3xj

Summary

swagger-typescript-api interpolates servers[0].url directly into a TypeScript string literal inside the HttpClient constructor body of the generated axios client (templates/base/http-clients/axios-http-client.ejs:71), without any escaping. A malicious URL containing a " closes the string literal and exposes the surrounding object-literal argument of axios.create({...}) to injection. A computed property key whose value is an IIFE executes arbitrary code every time new HttpClient() (or new Api(), which extends HttpClient) is constructed. The attacker controls the OpenAPI spec; the victim is any consumer of the generated client. Impact is arbitrary code execution with the importing process's privileges.

This is the axios sibling of the previously reported fetch-client RCE — same upstream variable (apiConfig.baseUrl, sourced from servers[0].url), same root cause class (raw <%~ %> interpolation of unescaped spec strings), different template file and different lifecycle frame (constructor body vs class-body static field). The single most maintainable fix — sanitizing apiConfig.baseUrl once at the source in src/code-gen-process.ts:591 — closes both at once.

Details

createApiConfig in src/code-gen-process.ts:591 sets the templated baseUrl from the spec without sanitization:

return {
  ...
  baseUrl: serverUrl,     // <-- serverUrl = swaggerSchema.servers[0].url, raw
  ...
};

The axios http-client template (templates/base/http-clients/axios-http-client.ejs:71) then interpolates that value into a TS string literal inside the HttpClient constructor body:

constructor({ securityWorker, secure, format, ...axiosConfig }: ApiConfig<SecurityDataType> = {}) {
    this.instance = axios.create({ ...axiosConfig, baseURL: axiosConfig.baseURL || "<%~ apiConfig.baseUrl %>" })
    ...
}

<%~ %> is Eta's raw, unescaped interpolation. The codebase's only escape function — escapeJSDocContent...