CVE-2026-103259
n8n before 2.39.6 and 2.40.x before 2.40.1 Session Token Leak via Dynamic Credentials
- State
- Published
- Severity
- 8.5 High
- Published
- Oct 1, 2026
- Updated
- Oct 1, 2026
- Reserved
- Sep 30, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 8.5 High | 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 | VulnCheck |
| 3.1 | 7.6 High | CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:H | VulnCheck |
Weaknesses
- CWE-863 Incorrect Authorization
Affected Products
| Product | Versions |
|---|---|
n8nn8n-io |
|
References
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