The detected rule focuses on identifying potential credential phishing attacks that utilize HTML smuggling techniques, particularly through excessive line break obfuscation. This method involves embedding JavaScript functions in HTML files that are designed to confuse security mechanisms by inserting numerous unnecessary line breaks within the code. The primary objective is to evade detection while maintaining the functionality of malicious scripts. The rule is triggered by analyzing inbound email attachments with specific characteristics such as file extensions (e.g., .html, .htm, .shtml, etc.), and by scanning for patterns that indicate the presence of excessive new line characters followed by sequences of alphanumeric characters. It employs regex matching techniques to detect these patterns alongside common JavaScript functions like 'decodeURIComponent', which are often associated with malicious payloads. The detection methods applied include archive, content, file, HTML, and JavaScript analysis, making this rule a robust defense against sophisticated phishing schemes that leverage file attachments.