Orval: RCE via OpenAPI path -> unescaped request-URL template literal (backtick breakout)

### Summary Orval emits the OpenAPI path into the generated request URL as a TEMPLATE LITERAL (`` `/users/...` ``) without escaping the backtick character. A path containing a backtick closes the template literal and injects a concatenation expression that is evaluated when the generated URL/request/key function is called, executing attacker-controlled code. Affects the axios, fetch, react-query, and swr clients. Verified on Orval 8.19.0; survives Orval's default OpenAPI validation. ### Details ```ts // generated URL builder (fetch client) return `/users/` + (globalThis.X = require("fs").writeFileSync("/marker","pwned")) + `/list`; ``` The backtick in the path terminates the `` `...` `` literal; `+ (<code>) +` runs as a live expression; a trailing backtick reopens a template literal so the file stays valid. The code runs whenever the generated request function, URL builder, or query-key function is called. This is distinct from Orval's four published CVEs: CVE-2026-22785 (`summary` -> MCP server), CVE-2026-23947 / CVE-2026-25141 (`x-enumDescriptions`), and CVE-2026-24132 (`const` -> mock files). This is a different field (the route path) and a different sink (the request-URL template literal), which those advisories and their fixes do not cover. ### PoC `reproduce.sh` (+ `make_spec.py`) attached: generates a fetch client with default validation, bundles it, calls the generated functions, and shows a marker file written. Verified on 8.19.0. ### Impact Code execution in any environment that calls a client generated from an attacker-controlled or attacker-influenced OpenAPI description (developer, CI, or the running application). ### Suggested fix Escape the path before emitting it into the URL template literal (escape backtick and `${`, or build the URL with an encoder that treats the path as data), and validate path characters. Source Code Location: https://github.com/orval-labs/orval Affected Packages: - npm:orval, affected < 8.21.0, patched in 8.21.0 CWEs: - CWE-94: Improper Control of Generation of Code ('Code Injection') - CWE-116: Improper Encoding or Escaping of Output - CWE-1336: Improper Neutralization of Special Elements Used in a Template Engine CVSS: - CVSS_V4: score 9.3, CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N References: - https://github.com/orval-labs/orval/security/advisories/GHSA-fg9p-mrxr-hvq7 - https://nvd.nist.gov/vuln/detail/CVE-2026-62681 - https://github.com/orval-labs/orval/pull/3692 - https://github.com/orval-labs/orval/commit/8ef1bfdf3f9bcaf9dabfbe2e42887f1c0e159ab6 - https://github.com/orval-labs/orval/releases/tag/v8.21.0 - https://github.com/advisories/GHSA-fg9p-mrxr-hvq7