{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0.9.0"
              },
              {
                "fixed": "0.9.7"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "bc24089391fab62a67d43b9081c22faed7e2b9cd"
            },
            {
              "fixed": "b15b026bf8a230e12f23ad1d1b48dc0d53ce010f"
            }
          ],
          "repo": "https://github.com/no-instructions/relay-server",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-9vp9-8q9j-8mqm"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-639",
      "CWE-863"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42889.json"
  },
  "details": "Relay adds real-time collaboration to Obsidian. Relay Server versions 0.9.0 through 0.9.6 contain an authentication bypass in the multi-document WebSocket endpoints. When authentication is configured, WebSocket connections without a token query parameter were incorrectly treated as having full server permissions. An unauthenticated network attacker who knows or guesses a document ID could connect to the document sync WebSocket and read or modify document contents without a valid document token. This vulnerability is fixed in 0.9.7.",
  "id": "CVE-2026-42889",
  "modified": "2026-08-04T11:31:09.843586805Z",
  "published": "2026-05-12T19:30:05.552Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42889.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/No-Instructions/relay-server/security/advisories/GHSA-9vp9-8q9j-8mqm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42889"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Relay Server WebSocket authentication bypass when token is omitted"
}