Vitest: Servers misapply `server.fs.deny`, serving `.env`, private keys, `.git`, and the API token file

{
  "id": "d18a0853a02cc44180fb2140f5fcb7af33b595e845ad7af30d48c467ceeacb84",
  "url": "https://osv.dev/vulnerability/GHSA-p458-7748-mcp3",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Vitest: Servers misapply `server.fs.deny`, serving `.env`, private keys, `.git`, and the API token file",
    "summary": "### Summary In Vitest 5, Vite's `server.fs.deny` is not applied as intended on Vitest's dev servers. Depending on the server, files that Vite refuses to serve by default (such as `.env`, private keys and certificates, `.npmrc`, and `.git`) or Vitest's own API token file (`.vitest-secret-token`) can be read over plain HTTP by a client that can reach the server. In Browser Mode with `test.projects`, a malicious website can also read `.env` values through the developer's browser. This only applies when Vitest runs an HTTP server, which happens with the UI (`--ui`), Browser Mode, or `api` enabled. Plain `vitest` and `vitest run` don't listen on any port and are not affected. The fix ships in `vitest`, and `@vitest/ui` and `@vitest/browser` are listed because they are what enables the affected setups. Both pin `vitest` to the same version as a peer dependency, so upgrading either one also requires the patched `vitest`. Users who enable `api` without `@vitest/ui` or `@vitest/browser` are also affected and should upgrade `vitest`. ### Details Vitest 5 adds its API token file to `server.fs.deny`, but neither server ended up with the intended list. That's because of two Vite behaviors. Vite applies its default deny list only when `server.fs.deny` is unset, and it compiles the list into a matcher during config resolution, so later changes to the array have no effect. | setup | listening server | Vite's default deny list | `.vitest-secret-token` | | ---------------------------------- | ",
    "evidence": "osv:GHSA-p458-7748-mcp3",
    "products": [
      {
        "name": {
          "value": "@vitest/ui",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.0.5",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "@vitest/browser",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.0.5",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "vite-plus",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "1.3.0",
            "evidence": "/affected/2/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "GHSA-p458-7748-mcp3",
      "aliases": [
        "CVE-2026-112948",
        "GHSA-p458-7748-mcp3"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "5.0.0-beta.6"
                },
                {
                  "fixed": "5.0.5"
                }
              ]
            }
          ],
          "package": {
            "name": "@vitest/ui",
            "purl": "pkg:npm/%40vitest/ui",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-p458-7748-mcp3/GHSA-p458-7748-mcp3.json"
          }
        },
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "5.0.0-beta.6"
                },
                {
                  "fixed": "5.0.5"
                }
              ]
            }
          ],
          "package": {
            "name": "@vitest/browser",
            "purl": "pkg:npm/%40vitest/browser",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-p458-7748-mcp3/GHSA-p458-7748-mcp3.json"
          }
        },
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "1.0.0-rc.0"
                },
                {
                  "fixed": "1.3.0"
                }
              ]
            }
          ],
          "package": {
            "name": "vite-plus",
            "purl": "pkg:npm/vite-plus",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-p458-7748-mcp3/GHSA-p458-7748-mcp3.json"
          }
        }
      ],
      "modified": "2026-10-21T20:01:39.862679779Z",
      "provider": "osv",
      "references": [
        "https://github.com/vitest-dev/vitest/security/advisories/GHSA-p458-7748-mcp3",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-112948",
        "https://github.com/vitest-dev/vitest/pull/11578",
        "https://github.com/vitest-dev/vitest/commit/28dc1edfb6ba5a181fe208576989063795aeadb3",
        "https://github.com/vitest-dev/vitest",
        "https://github.com/vitest-dev/vitest/releases/tag/v5.0.5"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-200",
          "CWE-552"
        ],
        "severity": "MODERATE",
        "github_reviewed": true,
        "nvd_published_at": "2026-10-20T16:17:05Z",
        "github_reviewed_at": "2026-10-21T19:57:00Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-112948",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 399305,
  "published_at": "2026-10-21T19:57:00+00:00"
}