Digital Forensic Certification Practice Exam

Which email header element helps protect senders and recipients from phishing and spamming?

1. DKIM

2. SPF

3. MIME

4. Message ID

The correct answer is: DKIM

The correct answer focuses on DKIM, which stands for DomainKeys Identified Mail. This email header element plays a critical role in email authentication by allowing the sender to sign their emails with a digital signature. When an email is sent, DKIM adds an encrypted signature in the header of the message, which can be validated by the recipient's email server against the sender's domain. This process helps in verifying that the email was indeed sent by the legitimate domain and has not been altered during transmission. As a result, it significantly reduces the chances of phishing attacks where an attacker impersonates a trustworthy sender to deceive recipients. By authenticating emails in this manner, DKIM helps improve overall email security and reduces unwanted spam. In contrast, while SPF (Sender Policy Framework) is also a method used to prevent email spoofing by defining which mail servers are permitted to send email on behalf of a domain, it does not provide the same level of verification for the integrity of the message itself. MIME (Multipurpose Internet Mail Extensions) is used for formatting messages that include multimedia content, rather than for authentication purposes. The Message ID is a unique identifier assigned to each email message and is useful for tracking but does not contribute to protection against phishing or spam.