CVE-2026-121419

SurrealDB from 3.1.0 before 3.3.0 contains an improper authentication vulnerability where the MCP BoundSubject fingerprint uses the access method name instead of per-user identity for JWT/Bearer access. Attackers with a valid low-privilege token for the same access method and a victim's mcp-session-id can hijack the session and execute MCP tools with the victim's roles and permissions.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/surrealdb/surrealdb/security/advisories/GHSA-pgh9-49q4-hqcx
https://www.vulncheck.com/advisories/surrealdb-3.1.0-before-3.3.0-mcp-session-hijack-via-boundsubject-collision

Configurations

No configuration.

History

03 Nov 2026, 15:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-11-03 15:17

Updated : 2026-11-03 15:17

NVD link : CVE-2026-121419

Mitre link : CVE-2026-121419

CVE.ORG link : CVE-2026-121419

JSON object : View

Products Affected

No product.

CWE

CWE-269

Improper Privilege Management

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