n8n CVE-2026-77075

Exploitation requires the attacker to hold at minimum a 'member' role in the target n8n instance with write access to create or edit nodes that contain resource-locator fields. The victim must actively open the affected node in the n8n visual editor - passive browsing of the workspace does not trigger the injection. The vulnerability is limited to the editor's link preview rendering path, so non-editor workflows (e.g., triggered executions without editor interaction) do not expose the flaw. Single-user n8n instances are not exploitable cross-user. Multi-tenant or team-deployed n8n instances where untrusted members share a workspace with privileged users represent the at-risk deployment model. The CVSS vector (PR:L/UI:A) confirms both prerequisites: low-privilege attacker authentication and active victim interaction are required.

The CVSS 4.0 score of 8.4 is well-supported by the vulnerability's mechanics: high confidentiality and integrity impact on the vulnerable system (VC:H/VI:H) reflects the ability to read and act within the victim's authenticated n8n session, including potentially accessing API credentials, external service tokens, and workflow data stored in n8n. Scope change metrics (SC:L/SI:L) indicate limited but real spillover to connected systems the victim's session can reach. The attack is low-complexity and requires only a low-privilege account, but critically depends on victim interaction (UI:A - the victim must open the affected node), which moderates real-world exploitation risk. There is no CISA KEV listing and no confirmed public exploit, making this a credible but not currently mass-exploited issue. EPSS data is not available in the provided input. The primary real-world risk is insider threat or multi-tenant n8n deployments where untrusted members share a workspace with privileged users; self-hosted single-user instances are unexploitable. The CVSS vector and description are consistent - no conflicts identified.

An attacker with a low-privilege member account in a shared n8n workspace creates or edits a workflow node containing a resource-locator field, storing a value with embedded n8n expression syntax that exfiltrates the opener's session token or triggers an API call using the victim's credentials. When a higher-privileged user (such as an owner or admin) opens that workflow node in the n8n editor, the injected expression executes in their authenticated browser session, potentially exposing their API keys, external service credentials, or allowing workflow manipulation under their identity. No public POC has been confirmed, but the attack mechanism is straightforward for anyone familiar with n8n's expression engine.