CVE-2026-103259

n8n before 2.39.6 and 2.40.x before 2.40.1 Session Token Leak via Dynamic Credentials

Published Oct 1, 2026 CVSS 4.0 · 8.5 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title n8n before 2.39.6 and 2.40.x before 2.40.1 Session Token Leak via Dynamic Credentials
First Time appeared N8n
N8n n8n
Weaknesses CWE-863
CPEs cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*
Vendors & Products N8n
N8n n8n
References
Metrics cvssV3_1

{'score': 7.6, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:H'}

cvssV4_0

{'score': 8.5, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:A/VC:H/VI:H/VA:H/SC:H/SI:L/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Oct 1, 2026, 7:27 PM
Reserved
Sep 30, 2026, 10:55 AM
Status
Deferred
Published
Oct 1, 2026, 11:17 AM
Modified
Oct 1, 2026, 8:17 PM