The 'GitHub Web Hook Modified' rule is designed to monitor changes to GitHub webhooks significantly impacting application security through automated exfiltration methods. The rule triggers when a webhook is created, modified, or deleted, helping detect potentially malicious activities related to unauthorized webhook manipulations. It employs logs from the 'GitHub.Audit' log type to detect the specified actions, which include creating and destroying hooks. The rule is set at a severity level of 'Info' as changes to webhooks might not always indicate malicious intent but can still be important for security monitoring. This helps security teams stay vigilant and maintain oversight on integrations that may pose a risk if not properly managed. The detection logic is validated through various test cases that ensure the rule functions correctly, correctly identifying valid hook events while ignoring unrelated actions, thus facilitating effective security management in GitHub environments.