CVE-2026-23947CWE-77

Orval MCP client is vulnerable to code injection via unsanitized x-enum-descriptions in enum generation

Critical · published January 20, 2026

CVSS v4.0
9.3
EPSS
1%
Percentile
57.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
9.3 · CRITICAL
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
EPSS
0.00832 · 57.2th percentile
Weakness
CWE-77 · Improper Neutralization of Special Elements used in a Command ('Command Injection')
Published
2026-01-20T00:19Z
EPSS history
Timeline
  • 20 JAN 00:19Z
    Orval MCP client is vulnerable to code injection via unsanitized x-enum-descriptions in enum generation
    cvelistv5