Email Spoofing

Email spoofing is a form of cyber attack where the sender of an email forges the header information to make it appear as though the email is from a legitimate or trusted source. This deceptive tactic is often used in phishing attacks to trick recipients into divulging sensitive information, downloading malicious software, or clicking on harmful links.

Key Characteristics

1. Forged Sender Address: The "From" field in the email header is manipulated to display a false email address, often resembling one from a trusted organization or contact.
2. Deceptive Content: The email content is crafted to appear legitimate, often mimicking the style and language of genuine communications from the impersonated entity.
3. Phishing Intent: The primary objective is usually to steal personal information, such as login credentials, or to install malware on the recipient’s device.

Common Techniques

1. SMTP Protocol Exploitation: Email spoofing exploits the Simple Mail Transfer Protocol (SMTP), which does not have built-in mechanisms to authenticate the sender’s identity.
2. Lookalike Domains: Attackers may register domain names that closely resemble legitimate ones, using subtle typos or variations.
3. Display Name Spoofing: The display name in the "From" field can be altered to appear as a trusted sender, such as a CEO or vendor, even if the actual email address is unfamiliar or suspicious. Many users only glance at the name, not the full address.
4. Reply-to Address Manipulation: Attackers can set a different "Reply-to" address in their spoofed emails, so even if the original looks real, responses are redirected to an attacker-controlled inbox.
5. Compromised Accounts: In some cases, attackers gain access to real email accounts and send phishing messages from legitimate addresses, making detection much more difficult.
6. Content Impersonation: Beyond just sender details, attackers often mimic brand language, logos, formatting, and signature blocks to make the email appear authentic and trustworthy.
7. Urgency and Fear Tactics: Spoofed emails commonly use urgent language ("Your account will be locked!") or emotional manipulation ("Important invoice attached") to pressure users into acting quickly without scrutiny.
8. Hyperlinked Text with Fake URLs: Clickable text in phishing emails might say "www.company.com" but link to a completely different — and dangerous — website designed to harvest credentials or infect devices.