High severity · published Oct 1, 2026
CVE-2026-103256
n8n before 2.39.6 and 2.40.x before 2.40.1 Credentials Leak via preAuthentication Hook
7.1
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 11% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
N8
n8n · n8n-io
before 2.39.6; 2.40.0 before 2.40.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-103256
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-103256
vendor-advisory
https://github.com/n8n-io/n8n/security/advisories/GHSA-gx6g-2hm7-c4xf
third-party-advisory
https://www.vulncheck.com/advisories/n8n-before-2.39.6-and-2.40-x-before-2.40.1-credentials-leak-via-preauthentication-hook
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