Vulnerability Report

CVE-2026-59208

Title: n8n JWT Sub Claim Authentication Bypass

Other

Proof Of Concept

No public PoC currently indexed for CVE-2026-59208.

CWE Category CWE-287
Published Date Jul 09, 2026
Modified Date Jul 14, 2026
Exploit Status Not Found
Score 7.6 CVSS v4.0
Exploit Probability (EPSS)
0.26%

Vulnerability Summary

CVE-2026-59208: n8n is an open source workflow automation platform. Prior to 2.27.4 and from 2.28.0 prior to 2.28.1, n8n instances configured with more than one trusted token-exchange issuer resolved external identities to local accounts using only the JWT sub claim and ignored the iss claim, allowing an attacker with a valid token from one trusted issuer and a sub matching a victim under another issuer to authenticate as that victim. This issue is fixed in versions 2.27.4 and 2.28.1.

Impacted Vendors

N
n8n 1

Reference Links

https://github.com/n8n-io/n8n/releases/tag/n8n%402.27.4 https://github.com/n8n-io/n8n/releases/tag/n8n%402.28.1 https://github.com/n8n-io/n8n/security/advisories/GHSA-mq3m-f8x3-579w
CVSS v4.0
Source Entity [email protected]
Severity HIGH
7.6
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
N/A
RAW VECTOR CVSS:4.0/AV:N/AC:L/AT:P/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 v3.1
Source Entity [email protected]
Severity MEDIUM
6.8
Attack Vector
NETWORK
Complexity
HIGH
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-59208 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity LOW
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:4.0/AV:N/AC:L/AT:P/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 Stack

No specific products linked.