{"id":"CVE-2026-63733","aliases":[],"url":"https://o3.security/vulnerability/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.","published":"2026-09-04T20:50:40Z","modified":"2026-09-04T21:00:07.664761419Z","cvss":{"score":4.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"surrealdb-core","fixedVersion":"3.2.0"}],"fix":{"url":"https://github.com/surrealdb/surrealdb/commit/1e4c3d743e1591f14f340cb627e56d98b6bd7fd7","label":"surrealdb/surrealdb@1e4c3d7"},"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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-04T21:00:07.664761419Z"}}