CVE-2026-121419

SurrealDB 3.1.0 before 3.3.0 MCP Session Hijack via BoundSubject Collision

Published Nov 3, 2026 CVSS 4.0 · 8.6 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title SurrealDB 3.1.0 before 3.3.0 MCP Session Hijack via BoundSubject Collision
First Time appeared Surrealdb
Surrealdb surrealdb
Weaknesses CWE-269
CPEs cpe:2.3:a:surrealdb:surrealdb:*:*:*:*:*:*:*:*
Vendors & Products Surrealdb
Surrealdb surrealdb
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'}

cvssV4_0

{'score': 8.6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Nov 9, 2026, 2:51 PM
Reserved
Nov 3, 2026, 12:29 PM
Status
Deferred
Published
Nov 3, 2026, 3:17 PM
Modified
Nov 9, 2026, 3:17 PM