Account Takeover API

Overview

Account takeover (ATO) is when a fraudster gains control of an account that belongs to a genuine customer. Fraudsters can monetize this in a number of ways, from making unauthorised transactions or selling the compromised accounts on to selling the personal information associated with the customer.

Phishing, spyware and malware can all be used to commit ATO attacks. However, for many merchants credential stuffing is the most common tactic used. Credential stuffing uses stolen username and password combinations to automate login requests in order to gain access to user accounts.

Following a breach, stolen credentials can be purchased on the darkweb or shared via cracking forums. Given that many people use the same password across multiple accounts, these credentials can then be used to launch a successful credential stuffing attack on other services.

Credential stuffing can be scripted by more skilled fraudsters. However, automated tools like Sentry MBA make credential stuffing very easy for anyone to commit.

How Ravelin Combats Account Takeover

Taking into account the nature of account takeover, Ravelin has introduced a number of different ways to combat the issue.

Machine learning

Using a custom machine learning model, we can distinguish between good and bad logins. We are able to look at the historic login behaviour for the customer and decide if the login looks unusual or not.

Rules

We can set account takeover specific rules around device, username and IP. For example, if the same device tries to access X accounts within a set time frame.

Breached Credentials

Credential stuffing relies on a list of username and password combinations. In order to mitigate against this, we maintain a breached credentials database. Calls can be made to the database either via the v3/login event at login or via /v2/lookup/credentials/check during registration or password change to verify if we’ve seen the credentials in the wild. Though we cannot guarantee that every breached credential will be in our database, this can go a long way to preventing ATO. You can also search for and view users that have logged in with credentials that appear in our database - providing additional context during investigations.

Collecting and surfacing login activity data

By leveraging data collected via v3/login event, we provide oversight of login activity within our dashboard. Login activity reporting is available to explore via our Analytics tool, making it easier to spot anomalies in ‘normal’ login activity across your customer base. In addition, you can interact with login data via a filterable login list and drill down to view login information for a specific customer on their customer profile.

Login Event

The point of login is a critical step in detecting account takeover. We want to prevent the malicious actor from being able to log in just like we want to prevent the fraudster from completing an order.

POST /v3/login?score=true

This is the endpoint used to tell Ravelin about every login attempt, both successful and unsuccessful. Unsuccessful logins can be important signals for an ATO attack. It will provide an ATO recommendation response if asked for via the query parameter score=true. Otherwise it will simply record the data without further processing.

{
  "timestamp": 1512828988826,
  "login": {
    "username": "jsmith123@example.com",
    "customerId": "abc-123-XYZ",
    "success": false,
    "authenticationMechanism": {
      "password": {
        "passwordHashed": "ef92b778bafe771e89245b89ecbc08a44a4e166c06659911881f383d4473e94f",
        "success": false,
        "failureReason": "UNKNOWN_USERNAME"
      },
      "social": {
        "success": false,
        "failureReason": "SOCIAL_FAILURE",
        "socialProvider": "facebook"
      },
      "oneTimeCode": {
        "success": false,
        "failureReason": "AUTHENTICATION_FAILURE"
      },
      "u2f": {
        "success": false,
        "failureReason": "INVALID_KEY"
      },
      "rsaKey": {
        "success": false,
        "failureReason": "INTERNAL_ERROR"
      },
      "smsCode": {
        "phoneNumber": "+447907283546",
        "success": false,
        "failureReason": "INVALID_CODE"
      },
      "magiclink": {
        "transport": "email",
        "phoneNumber": "+447907283546",
        "success": false,
        "failureReason": "RATE_LIMIT"
      },
      "recaptcha": {
        "success": false,
        "failureReason": "TIMEOUT"
      },
      "bioMetric": {
        "success": false,
        "failureReason": "BANNED_USER"
      },
      "pushNotification": {
        "success": false,
        "failureReason": "INTERNAL_ERROR"
      }
    },
    "app": {
      "name": "Our App Lite",
      "platform": "web",
      "domain": "us.brand.com"
    }
  },
  "device": {
    "deviceId": "65fc5ac0-2ba3-4a3b-aa5e-f5a77b845260",
    "ipAddress": "81.152.92.84",
    "language": "en-US",
    "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36",
    "model": "Pixel XL",
    "os": "android",
    "type": "phone",
    "manufacturer": "google",
    "location": {
      "country": "GBR",
      "postalCode": "E1 1AA",
      "latitude": 51.503252,
      "longitude": -0.127899,
      "addresseeName": "John Smith",
      "street1": "123 fake st.",
      "street2": "floor 4, flat 48",
      "neighbourhood": "Hackney",
      "zone": "1",
      "city": "London",
      "region": "California",
      "poBoxNumber": "1234"
    }
  },
  "location": {
    "country": "GBR",
    "postalCode": "E1 1AA",
    "latitude": 51.503252,
    "longitude": -0.127899,
    "addresseeName": "John Smith",
    "street1": "123 fake st.",
    "street2": "floor 4, flat 48",
    "neighbourhood": "Hackney",
    "zone": "1",
    "city": "London",
    "region": "California",
    "poBoxNumber": "1234"
  }
}

Above is the full login request object. This is similar to our /v2/login endpoint but with additional information regarding the authentication attempt. This request is expected to be sent after all successful and unsuccessful logins from your backend system.

Responses

Successful Example

You can see an example of a successful response from the /v3/login endpoint below. This response is identical to other responses given by the Ravelin platform for payment fraud endpoints. Note that we do provide payment fraud scores at login time as well. The Payment fraud and ATO responses are both included. Ensure you use the correct action when dealing with ATO vs. Payment Fraud.

{
  "status": 200,
  "success": "true",
  "timestamp": "2021-08-27T12:19:31Z",
  "data": {
    "customerId": "39f54f7c-8ed7-41f8-5260-09881f69f675",
    "action": "ALLOW",
    "score": 20,
    "source": "RAVELIN",
    "scoreId": "4fd50782-b9f7-48be-64e1-820c7cf6dd51",
    "ato": {
      "action": "PERMIT"
    }
  },
  "credentialStatus": {
    "passwordBreached": false,
    "usernameBreached": false
  },
  "customerChanges": [
    {
      "changeId": "9aa92ad0-ee23-4293-7fee-396dc738b195",
      "customerId": "39f54f7c-8ed7-41f8-5260-09881f69f675",
      "timestamp": "2021-08-27T12:19:31.035741497Z",
      "changeType": "DEVICE",
      "newValue": {
        "device": {
          "deviceId": "d61096b5-4ef8-4404-6666-eb9e8df1d754",
          "deviceType": "phone",
          "deviceManufacturer": "Samsung",
          "deviceModel": "SM-G960F",
          "deviceOS": "android",
          "ipAddress": "1c14:d7a:124f:3a00:400:cb7b:e4aa:af92",
          "userAgent": "Mozilla/5.0 (Linux; Android 10; SM-G960F) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.152 Mobile Safari/537.36",
          "timestamp": "2021-08-27T12:19:31.035741497Z"
        }
      },
      "previousValue": {
        "device": {
          "deviceId": "0c999b50-db07-46a0-629f-f55b89dc1dc0",
          "deviceType": "phone",
          "deviceManufacturer": "Apple",
          "deviceModel": "iPhone",
          "deviceOS": "ios",
          "ipAddress": "92.41.191.36",
          "userAgent": "Mozilla/5.0 (iPhone; CPU iPhone OS 14_4_2 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.3 Mobile/15E148 Safari/604.1",
          "timestamp": "2021-08-27T12:19:27.26181816Z"
        }
      },
      "verificationURL": "http://api/v2/change/verify?id=cmF2vbWVRlc3RCpzlhYTkyYWQwLRjNzM4YjN1cFsR1dHWVLWxZueELZWxpbnLTlvZ2ltNDI5My03ZmVlE5NQuLW3TCp2yM5NmZ0MjM==",
      "changeSetId": "aeb87294-a02d-4746-7d45-34770d51f308"
    }
  ]
}

Failure Example

You can see an example of a failed response from the /v3/login endpoint below. A failure response will indicate why the failure happened and will try to direct you to relevant documentation.

{
  "status": 500,
  "message": "Internal Server Error",
  "timestamp": "2021-08-27T12:19:31Z",
  "retryable": false
}

Action

Using the information supplied to Ravelin, logins and other events are categorised in one of three buckets: PERMIT WARN BLOCK

This information is sent in the response body to scored POST requests (with ?score=true) as defined above.

Requesting an action

Events sent to Ravelin using POST requests get an empty response body by default. The information is stored in our system and no further action is taken during the request. To force an immediate evaluation based on the information received up to and including an event add the ?score=true query parameter.

This will do two things:

1. Process the event payload
2. Force immediate recalculation of the action and return it

The score will be calculated based on the information in this event, and in all events previously received and met with a 200 OK status.

Suggested handling

The ?score=true query parameter is available on every event endpoint. This includes both ATO and Payment Fraud related endpoints. Specify it when you want to make a decision regarding a login attempt.

The most important field in the payload is action under the ATO object:

Other fields are provided for analytic and debugging purposes.

Credentials Check

POST /v2/lookup/credentials/check

Ravelin maintains a list of breached credentials that can be found in the public domain. At login, you can view whether the login attempt was using breached credentials by looking at the credentialStatus object within the /v3/login response.

You can use the database to check if a user is attempting to register a new account, or update an existing one, with credentials that have been seen in the wild via our v2/lookup/credentials/check endpoint. The below request is expected to be sent at password creation or update. The response will tell you if the username and/or password is found in our breached credential database.

Request

Passwords are extremely sensitive, so please do not send us plaintext passwords. Instead, please hash the password with SHA256 and HEX encode it before sending it. We do not store the hashed password, and discard it immediately after processing your request.

{
  "username": "jsmith123@example.com",
  "passwordHash": "6b86b273ff34fce19d6b804eff5a3f5747ada4eaa22f1d49c01e52ddb7875b4b"
}

Response

Successful Example

{
  "usernameBreached": true,
  "passwordBreached": true
}

There are three distinct flows where we check if a users credentials have been breached. For each flow, you may want to take a different action. Below we have outlined what we suggest for each flow.

Failure Example

{
  "status": 400,
  "traceId": "7fffffff9ed70f0101575067d-1925c9bf-2e34-422a-5e18-71a4ba379756",
  "timestamp": 1630073086
}

Authentication

While your backend is processing a login request, you can call our v3/login endpoint. Our response will indicate within the credential status object whether or not the username and password appear in Ravelin’s breached credential database.

...
"credentialStatus": {
    "usernameBreached": false,
    "passwordBreached": false
  },
...

...
"credentialStatus": {
    "usernameBreached": true,
    "passwordBreached": false
  },
...

...
"credentialStatus": {
    "usernameBreached": true,
    "passwordBreached": true
  },
...

Registration

At registration, you can call our v2/lookup/credentials/check endpoint. We will return the responses outlined below.

...
"credentialStatus": {
    "usernameBreached": false,
    "passwordBreached": false
  },
...

...
"credentialStatus": {
    "usernameBreached": true,
    "passwordBreached": false
  },
...

...
"credentialStatus": {
    "usernameBreached": true,
    "passwordBreached": true
  },
...

Password Updates

During an account update (e.g. forgot password, password change), you can call our v2/lookup/credentials/check endpoint. We will return the responses outlined below.

...
"credentialStatus": {
    "usernameBreached": false,
    "passwordBreached": false
  },
...

...
"credentialStatus": {
    "usernameBreached": true,
    "passwordBreached": false
  },
...

...
"credentialStatus": {
    "usernameBreached": true,
    "passwordBreached": true
  },
...

Reclaiming A Customer Account

POST /v2/reclaim

In cases where an account is reclaimed by the legitimate owner you need to notify us that the account has been secured. This will prevent the account from being blocked due to activity that happened while the account was compromised.

Accounts should be reclaimed if:

• A customer login has been blocked by Ravelin because of an ATO attempt and the password has been reset.
• A customer experiences and reports an ATO and the account has now been secured.
• An internal investigation identifies an ATO and results in the password being reset.

We strongly recommend notifying us about account reclaims only when you are sure that the 3rd party has lost access to the account. A reclamation on a customer account is taken into consideration during the decision making process when detecting account takeover. This means that at least for a short time, new logins are likely going to be permitted for that customer even in cases that might otherwise look suspicious.

If you use social login, you may need to consider unlinking social accounts as part of a reclaim. This is in the event that a fraudster logs in and links a social account which can then be used to continue accessing the account.

Request

A request has a limit of 1000 customers per batch. If more customers are present in the batch, we will respond with an error.

{
  "timestamp": 1512828988826,
  "customers": [
    {
      "customerId": "abc-123-ZYZ",
      "method": "Other",
      "reportedBy": "CUSTOMER",
      "atoEvents": [
        {
          "loginId": "42bd8af9-1ac2-7b2c-cd6a-a6a33c723510"
        }
      ]
    }
  ]
}

Response

Successful Example

On a successful request, we will respond with a message containing the number of accounts processed. This will always be the same as the amount provided to us in request payload.

{
  "status": 200,
  "message": "5 customer accounts reclaimed successfully"
}

Failure Example

{
  "status": 500,
  "message": "No customer accounts provided. Check https://developer.ravelin.com/apis/ato/#reclaiming for more details",
  "traceId": "7fffffff9ed70c8001b334488-a9363b6f-fb7d-4f52-7c76-a8d1ab42b712",
  "timestamp": 1630073727
}