SurrealDB: Cross-tenant access by authenticated namespace or database users

Summary

SurrealDB versions before 3.3.0 do not verify that the namespace or database selected by a caller matches the level at which the user authenticated. An attacker with a valid namespace- or database-level account in one tenant can select another tenant via the Surreal-NS/Surreal-DB headers on /sql or the RPC use method. The attacker can then read, create, modify and delete rows and read DEFINE PARAM values there, but only where the table PERMISSIONS allow it. The vendor rates the issue Critical; NVD scores it 8.6 (CVSS 4.0).

Affected

• SurrealDB versions before 3.3.0 (vendor: each affected v3.2.4 and earlier)
• Relevant for instances hosting several tenants with namespace- or database-level credentials
• Single-tenant deployments and root-level callers are not affected according to the vendor

Fixed in

• SurrealDB 3.3.0 and later
• Fixes are enabled by default in 3.3.0
• Backports to earlier branches: Unknown.

Workaround

• Until the upgrade, issue namespace-, database- and record-level credentials only to parties trusted with every tenant on the instance.
• Use separate deployments instead of namespace/database boundaries to isolate tenants.
• Replace PERMISSIONS FULL with a PERMISSIONS WHERE clause that checks the caller identity (for example $auth). This reduces exposure but does not restore the tenant boundary.
• Other configuration-based mitigations: Unknown.

Exploitation

• No known exploitation in the wild.
• No public proof of concept found.
• CISA SSVC: exploitation none, not automatable, partial technical impact.
• EPSS 0.00258 (low predicted probability, not evidence of exploitation).

Our recommendation

• Inventory all SurrealDB instances and their versions.
• Upgrade every instance below 3.3.0 to 3.3.0 or later after checking the vendor release notes.
• Until then, limit namespace and database credentials to parties trusted across all tenants and restrict network access to the database endpoints.
• Review table PERMISSIONS and DEFINE PARAM values on multi-tenant instances.
• Monitor logs for unusual use of the Surreal-NS/Surreal-DB headers or the RPC use method.

Public exploits iAttack code is publicly available (PoC on GitHub, Metasploit or Exploit-DB).

PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.

Research sources

• GitHub Security Advisory GHSA-w5v9-jc5f-5rmc github.com
• VulnCheck Advisory: SurrealDB before 3.3.0 Cross-Tenant Access www.vulncheck.com
• GitHub Security Advisory GHSA-vx2p-7hhm-wv62 (Surreal-NS/Surreal-DB headers with Basic authentication) github.com
• GitHub Security Advisory GHSA-2v9j-645m-pcrq (USE statement) github.com
• GitHub Security Advisory GHSA-3vw5-j55x-486h (RETURN FETCH for record users) github.com
• SurrealDB Release 3.3 surrealdb.com
• NVD record via Vulners vulners.com
• Positive Technologies PT-2026-110751 via Vulners vulners.com

Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 08:42.