Vulnerability · Published Oct 1, 2026 · Assigned by VulnCheck
CVE-2026-103256n8n before 2.39.6 and 2.40.x before 2.40.1 Credentials Leak via preAuthentication Hook
High 7.1
In plain English
A high-severity security flaw in n8n from n8n-io. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities).
Severity (CVSS 3.1)7.1High
Exploit odds (30 days)0.2%top 88.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected products (as reported)
Weakness: CWE-522 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N