CVE-2026-121419 json
SurrealDB 3.1.0 before 3.3.0 MCP Session Hijack via BoundSubject Collision
published 6d ago modified 11h ago also EUVD-2026-115951
- cvss
- 8.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 25%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- surrealdb surrealdb 3.3.0
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- total
- Assessed
- 11h ago
Exploit prediction
0.32% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/surrealdb/surrealdb/security/advisories/GHSA-pgh9-49q4-hqcx referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.6 | 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 |
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |
| CNA | 4.0 | 8.6 | 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 |
Affected products
- surrealdb surrealdb
Classification
- Weakness
-
- CWE-269 Improper Privilege Management
References
-
github.com
/surrealdb/surrealdb/security/advisories/GHSA-pgh9-49q4-hqcx
vendor-advisory, exploit
-
vulncheck.com
/advisories/surrealdb-3.1.0-before-3.3.0-mcp-session-hijack-via-boundsubject-collision
third-party-advisory
Sources
- CVE List CVE-2026-121419
- NVD CVE-2026-121419
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.