CVE-2026-63733: SurrealDB Writes Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-66r2-5gwj-gxm2",
  "modified" : "2026-09-04T20:50:40Z",
  "published" : "2026-09-04T20:50:40Z",
  "aliases" : [ "CVE-2026-63733" ],
  "summary" : "SurrealDB: Writes in a PERMISSIONS clause bypass table permissions",
  "details" : "A `PERMISSIONS ... WHERE` clause is evaluated with permission enforcement disabled, so it can't recurse into its own checks. But the clause could also contain data-modifying statements, and these ran with enforcement still off — so evaluating a permission check could write to tables the caller cannot write.\n\nFor example:\n\n```surql\nDEFINE TABLE post PERMISSIONS FOR update\n    WHERE (CREATE log SET at = time::now()) OR true;\n```\n\nAny user allowed to update a `post` now also creates a `log` record, even with no permission on `log`. The clause is evaluated once per matched record, so one statement can cause several writes.\n\n### Impact\n\nOnly databases with a `PERMISSIONS` clause that contains a write are affected; `FULL`, `NONE`, and read-only clauses are not.\n\nWhat an attacker **can** do:\n\n- With permission to perform the guarded operation (a low-privileged or record user is enough), write to tables in their own database that their permissions would otherwise forbid, by triggering an operation the clause guards.\n- Cause several writes from a single statement — the clause is evaluated once per matched record.\n- Trigger unintended events, cascades, or data corruption on those tables.\n\nWhat it **can't** do:\n\n- Escape the caller's own namespace and database — a permission clause cannot switch namespace or database.\n- Perform root- or namespace-level actions such as creating users; the caller's role still applies.\n- Read hidden data — this is an integrity issue, not disclosure.\n\n### Patches\n\nPermission clauses must now be read-only: defining or importing one that contains a write is rejected, and any write attempted while a clause is evaluated is blocked at runtime, including writes reached through a called function. Read-only clauses are unaffected.\n\n- Versions 3.2.0 and later are not affected by this issue.\n\n### Workarounds\n\nUsers unable to patch should consider the following workarounds:\n\n- Review your `PERMISSIONS` clauses and remove any containing `CREATE`, `UPDATE`, `DELETE`, `RELATE`, `INSERT`, or `UPSERT`.\n- Limit who can define schema and vet imported data — such a clause must be defined before it can be triggered.\n\n### Resources\n\n- [DEFINE TABLE … PERMISSIONS](https://surrealdb.com/docs/surrealql/statements/define/table)\n- [DEFINE FIELD](https://surrealdb.com/docs/surrealql/statements/define/field)\n- `fix(core): reject writes in PERMISSIONS clauses and block writes during permission evaluation` (included in SurrealDB 3.2.0)\n\n### Acknowledgements\n\nThank you to [sondt99](https://github.com/sondt99) for reporting this issue.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "surrealdb-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.2.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/surrealdb/surrealdb/security/advisories/GHSA-66r2-5gwj-gxm2"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-63733"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/surrealdb/surrealdb/commit/1e4c3d743e1591f14f340cb627e56d98b6bd7fd7"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/surrealdb/surrealdb/commit/afea699dfb3c8f274ab36861f8a95f5e98d82f1b"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/surrealdb/surrealdb"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/surrealdb/surrealdb/releases/tag/v3.2.0"
  }, {
    "type" : "WEB",
    "url" : "https://www.vulncheck.com/advisories/surrealdb-before-permissions-bypass-via-permissions-clause"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-863" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-09-04T20:50:40Z",
    "nvd_published_at" : null
  }
}