CVE-2026-77069 — n8n before 1.123.69 SSRF Protection Bypass via OAuth2
n8n before 1.123.69, 2.33.4, and 2.34.1 contains an SSRF protection bypass in the OAuth2 credential authorization-code-to-access-token exchange. While OAuth2 discovery and dynam…
Published: 2026-08-20 · CVSS: 2.3 · CVSS 4.0
n8n before 1.123.69, 2.33.4, and 2.34.1 contains an SSRF protection bypass in the OAuth2 credential authorization-code-to-access-token exchange. While OAuth2 discovery and dynamic-client-registration requests use n8n's SSRF-protected HTTP client, the token exchange uses a separate client with no SSRF guard. A user with credential-creation permissions can set the access-token URL to an internal address and complete the OAuth2 flow, causing n8n to send a fixed-shape token-exchange POST to that target and reflect its response body back to the attacker (limited to what the target returns to this specific request).
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7