Sygnum Authentication

generated: '2026-08-29'
method: probed
source: >-
  https://auth.sygnum.com/.well-known/openid-configuration (HTTP 200) plus the
  WWW-Authenticate challenge returned by https://api.sygnum.com/b2b/v1/available-scopes
  (HTTP 401) and the Access Management copy published in the developer.sygnum.com bundle
note: >-
  Sygnum publishes no OpenAPI, so this profile is not derived from a securitySchemes block.
  Every field below was read from a live anonymous probe of the bank's own hosts.
summary: >-
  OAuth 2.0 bearer tokens issued by Sygnum's Auth0 tenant at auth.sygnum.com. B2B partners
  self-service their machine clients in the developer portal's Access Management screen:
  each Auth0 client is created against a contract, given one or more credentials (a public
  key or certificate with a key identifier and an expiry time) and scoped to the Sygnum
  APIs it may call.
schemes:
- id: oauth2_client_credentials
  type: oauth2
  flow: clientCredentials
  in: header
  header: Authorization
  format: Bearer <access_token>
  token_endpoint: https://auth.sygnum.com/oauth/token
  issuer: https://auth.sygnum.com/
  jwks_uri: https://auth.sygnum.com/.well-known/jwks.json
  audience: per-contract Auth0 audience, shown in the portal's Access Management screen
  client_authentication:
  - private_key_jwt
  - client_secret_basic
  - client_secret_post
  - none
  note: >-
    The portal's credential form asks for a key identifier (kid), a PUBLIC KEY or
    CERTIFICATE and an expiry time, which is the private_key_jwt client-authentication
    method advertised in the discovery document.
  evidence:
    url: https://api.sygnum.com/b2b/v1/available-scopes
    http_status: 401
    www_authenticate: 'Bearer realm="auth.sygnum.com", error="invalid_token"'
- id: oidc_user_login
  type: openIdConnect
  openIdConnectUrl: https://auth.sygnum.com/.well-known/openid-configuration
  note: >-
    Human login to the developer portal itself. Authorization Code with PKCE (S256 and
    plain advertised); MFA challenge endpoint present.
  authorization_endpoint: https://auth.sygnum.com/authorize
  userinfo_endpoint: https://auth.sygnum.com/userinfo
  end_session_endpoint: https://auth.sygnum.com/oidc/logout
  revocation_endpoint: https://auth.sygnum.com/oauth/revoke
grant_types_supported:
- client_credentials
- authorization_code
- refresh_token
- implicit
- password
- urn:ietf:params:oauth:grant-type:device_code
- urn:ietf:params:oauth:grant-type:token-exchange
- urn:ietf:params:oauth:grant-type:jwt-bearer
token_signing_algs:
- RS256
- RS384
- PS256
pkce_methods:
- S256
- plain
mtls: false
api_keys:
  used: partial
  note: >-
    Portal copy ("the API key will appear in the overview section of the specific requested
    API in the developer portal") indicates a per-API key is also surfaced to onboarded
    clients alongside the OAuth client. The key's transport header is not published
    publicly and was not observed on any anonymous response.
docs: https://developer.sygnum.com/how-to-connect
gated:
  is_gated: true
  detail: >-
    The specification downloads and the Access Management screen require an authenticated
    Sygnum client login; only the OIDC discovery document and the 401 challenge are
    anonymous.