CVE-2026-103259

n8n versions before 2.39.6 and 2.40.0 before 2.40.1 contain a session token leakage vulnerability in the Dynamic Credentials authorize and revoke endpoints. Attackers with resolver registration capability can capture collaborators' session tokens by setting a fallback resolver to an attacker-controlled endpoint during the account connection flow, enabling unauthorized credential access.

CVSS v3 7.6 HIGH

7.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.0 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required HIGH

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/n8n-io/n8n/security/advisories/GHSA-rx55-8qhx-4hwx
https://www.vulncheck.com/advisories/n8n-before-2.39.6-and-2.40-x-before-2.40.1-session-token-leak-via-dynamic-credentials

Configurations

No configuration.

History

01 Oct 2026, 11:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-01 11:17

Updated : 2026-10-01 20:17

NVD link : CVE-2026-103259

Mitre link : CVE-2026-103259

CVE.ORG link : CVE-2026-103259

JSON object : View

Products Affected

No product.

CWE

CWE-863

Incorrect Authorization

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