Operation uses password grant flow in OAuth2 authentication
Issue ID: operation-securityrequirement-oauth2-password
Average severity: Minimal
Description
The API operation uses resource owner password credentials grant flow in OAuth2 authentication. This flow has been deprecated by OAuth Best Current Practice and must not be used.
For more details, see the OpenAPI Specification.
Example
The following is an example of how this type of risk could look in your API definition:
{
"schemes": [
"https"
],
// ...
"securityDefinitions": {
"OAuth2": {
"type": "oauth2",
"flow": "password",
"scopes": {
"write": "modify objects in your account",
"read": "read objects in your account"
},
"tokenUrl": "https://example.com/oauth/token"
}
},
// ...
"paths": {
"/pets": {
"post": {
"description": "Creates a new pet in the store",
"operationId": "addPet",
"security": [
{
"OAuth2": [
"write",
"read"
]
}
]
// ...
}
}
}
}
Possible exploit scenario
The resource owner password grant flow in OAuth2 is highly dangerous, because it exposes the credentials of the resource owner to the client. Even in the best case, this expands the attack surface and also normalizes insecure behavior (entering your credentials somewhere else than the authorization server).
Remediation
Do not use resource owner password credentials grant flow in OAuth 2 authentication.
{
"schemes": [
"https"
],
// ...
"securityDefinitions": {
"OAuth2": {
"type": "oauth2",
"flow": "accessCode",
"scopes": {
"read": "read objects in your account",
"write": "modify objects in your account"
},
"authorizationUrl": "https://example.com/oauth/authorize",
"tokenUrl": "https://example.com/oauth/token"
}
},
// ...
"paths": {
"/pets": {
"post": {
"description": "Creates a new pet in the store",
"operationId": "addPet",
"security": [
{
"OAuth2": [
"write",
"read"
]
}
]
// ...
}
}
}
}