Vulnerability details
CVE-2026-103259
n8n-io n8n
n8n before 2.39.6 and 2.40.x before 2.40.1 Session Token Leak via Dynamic Credentials
CVSS 4.0
8.5High
Official 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.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 8.5High | 4.0 | CVEProject cvelistV5 (CNA) (VulnCheck) | 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 |
| 7.6High | 3.1 | CVEProject cvelistV5 (CNA) (VulnCheck) | CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| n8n-io | n8n | v < 2.39.6 | CVEProject cvelistV5 (CNA) |
| n8n-io | n8n | 2.40.0 ≤ v < 2.40.1 | CVEProject cvelistV5 (CNA) |
References and advisories
2
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Details
- Published
- 2026-10-01
- Last updated
- 2026-10-01
- State
- Published
- Assigner (CNA)
- VulnCheck
Exploit prediction (EPSS)
0.23%
Probability of exploitation in 30 days
15%
Percentile (among all CVEs)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- None
- Technical impact
- Total
Weaknesses (CWE)
- CWE-863Incorrect Authorization