CVE-2026-103259 (GCVE-0-2026-103259)

Vulnerability from cvelistv5 – Published: 2026-10-01 10:42 – Updated: 2026-10-01 19:27
VLAI
Title
n8n before 2.39.6 and 2.40.x before 2.40.1 Session Token Leak via Dynamic Credentials
Summary
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.
Severity
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
7.6 (High)
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-01 19:27 UTC
CWE
  • CWE-863 - Incorrect Authorization
Assigner
References
Impacted products
Vendor Product Version CPE status
n8n-io n8n Affected: 0 , < 2.39.6 (semver)
Affected: 2.40.0 , < 2.40.1 (semver)
    cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*
    cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-16 00:00
Credits
nlgbao1340
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Nomenclature

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