n8n EUVD-2026-112378

Requires an authenticated n8n user who holds execution-read permission but is denied credential-read permission (the exact trust boundary the flaw crosses). The instance must run a SeaTable Trigger node in poll mode, and a poll request to obtain the base access token must have actually failed - only then is the raw HTTP error, including the Authorization header with the API token, written into the error execution record. Limiting factors: exploitation is impossible without a prior poll failure having been recorded, requires existing low-privilege access to the n8n instance (PR:L, not remote-unauthenticated), and only affects deployments actually using SeaTable poll triggers on vulnerable versions (n8n < 1.123.85, 2.x < 2.43.5, 2.44.x < 2.44.1).

This is a moderate-severity information-disclosure flaw (CWE-532), and the signals are internally consistent rather than conflicting. The CVSS 4.0 vector (AV:N/AC:L/AT:P/PR:L/UI:N) indicates a network-reachable issue but one that requires an already-authenticated low-privilege user (PR:L) and a specific precondition (AT:P) - namely that a SeaTable poll request actually failed and wrote raw headers into error execution data. This is not a remote-unauthenticated break-in; it is a privilege/trust-boundary bypass where a user who can read executions but is denied credential access recovers a secret they should not see. The vuln.today decision label is 'this_month' (not act_now/emergency), which matches the absence of CISA KEV listing and the lack of any provided EPSS score or PoC/exploit reference. No active exploitation is claimed and no public exploit is referenced in the input. The direct technical impact is limited (token disclosure, VC:L), but the 4.0 subsequent-system metrics (SC:H/SI:H) correctly capture that the leaked token grants confidentiality and integrity access to the connected SeaTable base - a real lateral-impact concern. Net: a legitimate patch-this-cycle issue for n8n operators who run SeaTable poll triggers and have users with execution-read-but-not-credential-read roles, but not an internet-facing emergency. Note that EPSS and KEV data are absent from the input, so widespread-exploitation probability could not be quantified.

An n8n operator grants a team member read access to workflow executions but withholds access to stored credentials. A SeaTable Trigger node running in poll mode experiences a failed base-token request, and n8n saves the raw HTTP error - including the Authorization header carrying the API token - into the error execution record. The low-privilege user opens that execution, reads the token out of the stored request headers, and uses it to access and modify the connected SeaTable base. No public exploit code is referenced in the input; exploitation is trivial manual inspection requiring only existing execution-read access.