Vitest: Code injection via unauthenticated manual mock registration

{
  "id": "ec85b2279047b6e4a0cf98d0d47f201f39436f34294e9c0d0bc03bd6fe53e264",
  "url": "https://osv.dev/vulnerability/GHSA-qxg6-89mg-rqv8",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Vitest: Code injection via unauthenticated manual mock registration",
    "summary": "### Summary `@vitest/mocker`'s `interceptorPlugin` accepts mock registrations on Vite's dev-server WebSocket with no authentication, and interpolates the mock's `url` into generated module source without escaping. A client that can reach the dev server can make it serve arbitrary JavaScript in place of any project module, which then runs in the developer's browser on the dev-server origin. Same handler and same unauthenticated caller as GHSA-82fw-gwwq-j7x9; that fix (`8ff9b9a9efca7c6cfd5243569440de8d7a33aec4`, PR #10972) hardened only the `redirect` branch and left the `manual` branch reaching the unescaped generator. ### Patches Fixed in `@vitest/mocker` 5.0.3, released on 2026-09-30 (PR #11377), and backported to 4.1.12. `createManualModuleSource` now serializes the module URL and the export names with `JSON.stringify`, so a registered mock cannot change the generated code. Projects that call `mockerPlugin()` or `interceptorPlugin()` directly need `@vitest/mocker` 4.1.12 or 5.0.3. ### Details `packages/mocker/src/utils.ts:6-9` builds module source by string interpolation: ```ts export function createManualModuleSource(moduleUrl: string, exports: string[], globalAccessor = '\"__vitest_mocker__\"'): string { const source = ` const __factoryModule__ = await globalThis[${globalAccessor}].getFactoryModule(\"${moduleUrl}\"); ` ``` `moduleUrl` lands inside a double-quoted JavaScript string with no escaping or validation. `packages/mocker/src/node/interceptorPlugin.ts:66-93` feeds it s",
    "evidence": "osv:GHSA-qxg6-89mg-rqv8",
    "products": [
      {
        "name": {
          "value": "@vitest/mocker",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "4.1.12",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "@vitest/mocker",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.0.3",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "GHSA-qxg6-89mg-rqv8",
      "aliases": [
        "CVE-2026-112949",
        "GHSA-qxg6-89mg-rqv8"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "2.1.0-beta.7"
                },
                {
                  "fixed": "4.1.12"
                }
              ]
            }
          ],
          "package": {
            "name": "@vitest/mocker",
            "purl": "pkg:npm/%40vitest/mocker",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-qxg6-89mg-rqv8/GHSA-qxg6-89mg-rqv8.json"
          }
        },
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "5.0.0-beta.1"
                },
                {
                  "fixed": "5.0.3"
                }
              ]
            }
          ],
          "package": {
            "name": "@vitest/mocker",
            "purl": "pkg:npm/%40vitest/mocker",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-qxg6-89mg-rqv8/GHSA-qxg6-89mg-rqv8.json"
          }
        }
      ],
      "modified": "2026-10-21T20:01:39.911013327Z",
      "provider": "osv",
      "references": [
        "https://github.com/vitest-dev/vitest/security/advisories/GHSA-qxg6-89mg-rqv8",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-112949",
        "https://github.com/vitest-dev/vitest/commit/15cc006aa9f8683dc5f7e895d011fa7dc751ce35",
        "https://github.com/vitest-dev/vitest/commit/b825313243dc55757e8d7c0f9e7a792135e13473",
        "https://github.com/vitest-dev/vitest",
        "https://github.com/vitest-dev/vitest/releases/tag/v4.1.12",
        "https://github.com/vitest-dev/vitest/releases/tag/v5.0.3"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-116",
          "CWE-306",
          "CWE-94"
        ],
        "severity": "MODERATE",
        "github_reviewed": true,
        "nvd_published_at": "2026-10-20T16:17:05Z",
        "github_reviewed_at": "2026-10-21T19:54:26Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-112949",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 399306,
  "published_at": "2026-10-21T19:54:26+00:00"
}