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

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Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, an unescaped backtick in an OpenAPI path is emitted into request URL template literals generated for axios, fetch, react-query, and SWR clients without safe encoding. This permits attacker-controlled JavaScript to be evaluated when a generated request, URL-builder, or query-key function is called, resulting in code execution in the developer, CI, test, or application environment. The affected code is packages/core/src/getters/route.ts and route generation consumers. This issue is fixed in version 8.21.0.

Source published

19 Aug 2026 17:31:02 UTC

Source modified

21 Aug 2026 19:42:09 UTC

Saved here

23 Oct 2026 15:48:27 UTC

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CVE Program Terms of Use

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CVSS 4.0 · 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

Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, an unescaped backtick in an OpenAPI path is emitted into request URL template literals generated for axios, fetch, react-query, and SWR clients without safe encoding. This permits attacker-controlled JavaScript to be evaluated when a generated request, URL-builder, or query-key function is called, resulting in code execution in the developer, CI, test, or application environment. The affected code is packages/core/src/getters/route.ts and route generation consumers. This issue is fixed in version 8.21.0.

Source published

Aug 19, 2026, 5:31:02 PM (timezone not stated)

Source modified

Aug 21, 2026, 7:42:09 PM (timezone not stated)

Saved here

14 Nov 2026 07:10:16 UTC

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ENISA EUVD · source terms and attribution apply

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Source: euvd · ENISA EUVD · source terms and attribution apply. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

EUVD CVSS 4.0 · 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

Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, an unescaped backtick in an OpenAPI path is emitted into request URL template literals generated for axios, fetch, react-query, and SWR clients without safe encoding. This permits attacker-controlled JavaScript to be evaluated when a generated request, URL-builder, or query-key function is called, resulting in code execution in the developer, CI, test, or application environment. The affected code is packages/core/src/getters/route.ts and route generation consumers. This issue is fixed in version 8.21.0.

Source published

19 Aug 2026 18:16:54 UTC

Source modified

9 Sep 2026 21:20:38 UTC

Saved here

25 Oct 2026 14:19:28 UTC

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Source: nvd · NIST NVD usage terms; underlying source attribution retained. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 4.0 · [email protected] · Secondary · 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

### 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 published

3 Sep 2026 19:17:32 UTC

Source modified

18 Sep 2026 05:30:05 UTC

Saved here

24 Oct 2026 13:17:17 UTC

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GitHub Advisory Database · CC-BY-4.0

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Source: osv · GitHub Advisory Database · CC-BY-4.0. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS_V4 · 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

Publisher rating · CRITICAL