Email Spoofing is a common practice where threat actors impersonate a sender’s domain or address to trick victims into thinking the email is legitimate. The technique is mainly found in phishing emails where the attacker tries to convince the recipient to click a malicious link or attachment, give personal information, or send money.
What is Email Spoofing?
Email spoofing exploits vulnerabilities in the Simple Mail Transfer Protocol (SMTP), which is the standard protocol for sending emails across the internet. Attackers manipulate the “From” field in the email header to make it appear it is coming from a legitimate company or person.
Email Authentication: SPF, DKIM, and DMARC
To safeguard from email spoofing, SPF, DKIM, and DMARC are used to prove the legitimacy of emails.
- SPF (Sender Policy Framework) is a DNS-based email validation system that allows domain owners to specify which IP addresses are authorized to send emails on behalf of the domain. Companies would put the IP addresses of their email servers in their DNS settings as authorized servers that send legitimate emails from them.
- DKIM (DomainKeys Identified Mail) increases email security by adding a digital signature to outgoing emails. This signature is generated using cryptographic keys stored in the sender’s DNS records. Recipients can verify the authenticity of the email by comparing the DKIM signature with the sender’s published public key, ensuring that the message has not been altered in transit and originates from a legitimate source.
- DMARC (Domain-based Message Authentication, Reporting, and Conformance) provides domain owners with greater control over their email authentication policies. Organizations can use DMARC to instruct email providers on how to handle emails that fail SPF or DKIM checks.
All companies should consider implementing SPF, DKIM, and DMARC to help provide email security. Recipients then could check the authentication results by using tools to analyze the email headers. Organizations can strengthen their defenses against spoofing attacks, protect sensitive information, and uphold the integrity of their email communications by implementing these email authentication methods.
*Article was written with the assistance of OpenAI”s ChatGPT*
