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.
{
"cna_assigner": "VulnCheck",
"cwe_ids": [
"CWE-863"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/103xxx/CVE-2026-103259.json"
}{
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "2.39.6"
},
{
"introduced": "2.40.0"
},
{
"fixed": "2.40.1"
}
],
"source": "AFFECTED_FIELD"
}