Lack of Email Address Input Validation on privacy-request/notification API Endpoint

[daveqnet]

Bug Description

The Fides API allows to define alerts which in case of some errors in processing send proper notifications to recipients. The API was found to not validate the email addressed on the backend, thus it can potentially result in uncaught errors and unexpected notifications failures.

Steps to Reproduce

API Request

PUT /api/v1/privacy-request/notification HTTP/2
Host: <redacted>.ethyca.com
Content-Length: 68
Sec-Ch-Ua: "Not:A-Brand";v="99", "Chromium";v="112"
Unescape-Safestr: true
Sec-Ch-Ua-Mobile: ?0
Authorization: Bearer eyJh<redacted>
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/112.0.5615.50 Safari/537.36
Content-Type: application/json
Access-Control-Allow-Origin: *
X-Fides-Source: fidesops-admin-ui
Sec-Ch-Ua-Platform: "Linux"
Accept: */*
Origin: https://<redacted>.ethyca.com
Sec-Fetch-Site: same-origin
Sec-Fetch-Mode: cors
Sec-Fetch-Dest: empty
Referer: https://<redacted>.ethyca.com/privacy-requests
Accept-Encoding: gzip, deflate
Accept-Language: en-US,en;q=0.9

{"email_addresses":["INVALID ADDRESS1","INVALID ADDRESS2"],"notify_after_failures":1}

API Response

HTTP/2 200 OK
Date: Wed, 16 Aug 2023 09:04:37 GMT
Content-Type: application/json
Content-Length: 85
Server: uvicorn
X-Ratelimit-Limit: 1000
X-Ratelimit-Remaining: 998
X-Ratelimit-Reset: 1692176712
Retry-After: Wed, 16 Aug 2023 09:05:12 -0000
Access-Control-Allow-Credentials: true
Access-Control-Allow-Origin: https://<redacted>.ethyca.com
Vary: Origin

{"email_addresses":["INVALID ADDRESS1","INVALIDADDRESS2"],"notify_after_failures":1}

Expected behavior

• The request should be rejected with an error when the invalid email address fails input validation.
• Implement input validation and consider adding a test notification feature to verify the settings are working correctly.

Screenshots

n/a

Environment

Version: 2.18.0 (repro'd on nightly 2.21.0rc0.post0.dev22)
OS: Kubernetes (AWS EKS v1.27.3-eks-a5565ad)
Python Version: 3.10.12
Docker Version: containerd://1.6.19

Additional context

n/a

[batman1911]

Please assign this to me. Also, can you please add the label "hacktoberfest" ?