CVE-2026-121419
SurrealDB 3.1.0 before 3.3.0 MCP Session Hijack via BoundSubject Collision
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
8.6
SurrealDB 3.1.0 before 3.3.0 MCP Session Hijack via BoundSubject Collision
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.
- Record
CVE-2026-121419- CVSS 4.0
- 8.6 High
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 - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-269
- Updated
- 2026-11-03
EUVDEUVD-2026-115951
8.6
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.
- Record
EUVD-2026-115951- CVSS 4.0
- 8.6 High
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 - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-hprh-85vv-3jpq
8.6
SurrealDB from 3.1.0 before 3.3.0 contains an improper authentication vulnerability where the MCP...
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.
- Record
GHSA-hprh-85vv-3jpq- CVSS 4.0
- 8.6 High
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-269
- Updated
- 2026-11-03
NVD
8.6
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.
- Record
CVE-2026-121419- CVSS 4.0
- 8.6 High
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-269
- Updated
- 2026-11-03
OSV
8.6
SurrealDB 3.1.0 before 3.3.0 MCP Session Hijack via BoundSubject Collision
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.
- Record
CVE-2026-121419- CVSS 4.0
- 8.6 High
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 - Weakness
- CWE-269
- Updated
- 2026-11-05
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, references | OSV | |
| published | EUVD, NVD | |
| facts, published | EUVD | |
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-121419 is a high vulnerability (CVSS 8.6) in Surrealdb, published November 3, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.32%, the 25th percentile. No source names a fixed version.
References
github.com/surrealdb/surrealdb/security/advisories/GHSA-pgh9-49q4-hqcx
vulncheck.com/advisories/surrealdb-3.1.0-before-3.3.0-mcp-session-hijack-via-boundsubject-collision
nvd.nist.gov/vuln/detail/CVE-2026-121419
github.com/advisories/GHSA-hprh-85vv-3jpq
github.com/CVEProject/cvelistV5/tree/main/cves/2026/121xxx/CVE-2026-121419.json