CVE-2026-65594
MEDIUM
MEDIUM
Priority: 0.02
BB Relevance:
60/100
Published: 2026-07-22
Modified: 2026-10-29
First seen: 2026-10-29
Status: active
Attack Surface
Network
Low Complexity
No Interaction
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
Low
UI:
None
AT:
Present
VC:
Low
VI:
Low
VA:
None
Description
n8n before 2.29.8 and 2.30.x before 2.30.1 (affected from 2.27.0, when the OAuth 2.1 consent and token-issuance flow was introduced) does not verify that the authenticated user has access to the workflow referenced as the OAuth resource. On instances with at least one active MCP Server Trigger workflow configured with n8n OAuth2 authentication, a member-level user can register an OAuth client, self-approve consent for another user's workflow, and obtain a valid token. The workflow then runs in the owner's project context with the owner's stored credentials, and the attacker can set tool inputs and read outputs (potentially including data from the owner's connected integrations), breaking user and project isolation.
Weakness Classification (1)
Affected Software (8)
References & Advisories (2)
Third Party Advisory
Mitigation
Vendor Advisory