CVE-2026-103256

n8n before 2.39.6 and 2.40.x before 2.40.1 Credentials Leak via preAuthentication Hook

Published Oct 1, 2026 CVSS 4.0 · 7.1 High EPSS < 1% KEV · Not listed
Description
n8n versions before 2.39.6 and 2.40.0 before 2.40.1 contain a credentials leak vulnerability in the Wekan and Baserow username-and-password credentials that sends unencrypted passwords to unvalidated hosts. Attackers with credential update permissions can modify the host field to receive account passwords at arbitrary hosts, bypassing domain validation controls.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, '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 credentials leak vulnerability in the Wekan and Baserow username-and-password credentials that sends unencrypted passwords to unvalidated hosts. Attackers with credential update permissions can modify the host field to receive account passwords at arbitrary hosts, bypassing domain validation controls.
Title n8n before 2.39.6 and 2.40.x before 2.40.1 Credentials Leak via preAuthentication Hook
First Time appeared N8n
N8n n8n
Weaknesses CWE-522
CPEs cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*
Vendors & Products N8n
N8n n8n
References
Metrics cvssV3_1

{'score': 7.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N'}

cvssV4_0

{'score': 7.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:L/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Oct 1, 2026, 1:28 PM
Reserved
Sep 30, 2026, 10:55 AM
Status
Deferred
Published
Oct 1, 2026, 11:17 AM
Modified
Oct 1, 2026, 2:17 PM