---
title: "CVE-2026-71867: Orval: RCE via schema property name -> computed-property-key injection in the MSW mock generator"
url: https://erroneo.us/security/cve/CVE-2026-71867/
description: "CVE-2026-71867 (orval (npm)): Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, a…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-08-19
date_modified: 2026-09-03
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-71867"
kev: false
cvss: 9.3
epss: 0.00653
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-71867: Orval: RCE via schema property name -> computed-property-key injection in the MSW mock generator

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.7% , percentile 51: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 51% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes orval (npm) < 8.21.0, fixed in 8.21.0 . Check your lockfile, including transitive dependencies.

## What it is

Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, a single quote in a schema property name is emitted into single-quoted object keys in generated MSW mock factories without safe encoding. This permits attacker-controlled JavaScript to be evaluated when the generated mock factory is called by tests or an MSW handler, resulting in code execution in the developer, CI, test, or application environment. The affected code is packages/core/src/getters/keys.ts function getKey and MSW mock generation. This issue is fixed in version 8.21.0.

## Affected packages

- npm `orval` < 8.21.0 → fixed: 8.21.0

## Affected products (CVE record)

- orval-labs orval: < 8.21.0

## Severity

- GitHub_M 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`
- GitHub 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`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.65% probability of exploitation activity in the next 30 days; percentile 51.

## Sources

- [GitHub Advisory GHSA-2w86-xfrc-g85r](https://github.com/advisories/GHSA-2w86-xfrc-g85r)
- [CVE.org record CVE-2026-71867](https://www.cve.org/CVERecord?id=CVE-2026-71867)
- [NVD entry CVE-2026-71867](https://nvd.nist.gov/vuln/detail/CVE-2026-71867)
- [github.com](https://github.com/orval-labs/orval/security/advisories/GHSA-2w86-xfrc-g85r)
- [github.com](https://github.com/orval-labs/orval/pull/3692)
- [github.com](https://github.com/orval-labs/orval/commit/8ef1bfdf3f9bcaf9dabfbe2e42887f1c0e159ab6)
- [github.com](https://github.com/orval-labs/orval/releases/tag/v8.21.0)

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Source page: https://erroneo.us/security/cve/CVE-2026-71867/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt