CVE-2026-77069

Summary

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).

Affected Software

VendorProductVersion RangeStatus
n8n-ion8n0 < 1.123.69affected
n8n-ion8n1.123.69unaffected
n8n-ion8n0 < 2.34.1affected
n8n-ion8n2.34.1unaffected
n8n-ion8n0 < 2.33.4affected
n8n-ion8n2.33.4unaffected

Weaknesses

  • CWE-918: Server-Side Request Forgery (SSRF)

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References