March 13, 2023
You’ve gotten multiple e-mails from unknown sources or people you know. Familiar addresses may meet among fraudsters. You likely wonder how that may happen. Yes, an attacker can use a familiar address of the sender, replacing a single symbol or letter. For example [email protected] instead of [email protected]. If you don’t look carefully at the address bar, you might not notice it. Next thing you know, you open a letter - you see a request to send your data to that user, and you humbly agree to it. And then - you sent the data to the intruder. How do you not fall for it, and what is it in general?
Key takeaway: Email Spoofing is a way to deceive a user by stealing sensitive user information, distributing malware, or spreading phishing attacks. To apply all this, the attacker needs your logins, passwords from your accounts, bank card numbers, and so on. Hackers make spoofing attacks by falsifying the headers and address lines of the e-mail so that the user can take it for granted.
How does it work?
How e-mail systems are designed affects the e-mail sender address substitution. Servers cannot detect outgoing mail because the client application assigns the sender address to outgoing messages. In this way, hackers can use their manipulation, pressure the user, and cause pity to themselves through messages with a fake header because the user will think that he is sending this information to his relatives and relatives, or the bank that he uses.
To filter and detect fake messages and protect against malicious software, it is necessary to have security protocols, but unfortunately, not all servers have this. In this case, users need to be careful and check every e-mail header attached to the message to avoid the risk of an attack by the attacker. Another thing worth keeping in mind is the list of messages you are waiting for. Crooks may commit chaotic mailing, hoping that victims will be reckless enough to ignore that they must not receive such messages.
Reasons for Email Spoofing
The attacker uses a spoofing method for his evil intentions for various reasons. These reasons are common, even from some banal sides. However, the final targets were defined long ago and haven't been changed yet. Let’s look at the most common ones:
- Phishing. In this case, the e-mail address of the services is used. The attacker convinces the victim to switch to the phishing resource. He further asks her to enter the data of her account or go to the other malicious link that will either infect the victim's PC or make it vulnerable for further exploit usage.
- Identity theft. To steal more data (medical references, card passwords), you should pretend to be a victim or someone else. Identity theft may also be useful for further spear phishing attacks.
- Avoiding spam filters. To avoid being blacklisted, spammers are diligently trying to switch between e-mail addresses. Still, that delays the ban.
- Anonymity. In this case, the sender does not want to hurt someone. He tries to hide his identity. Such a message may still have a stolen style, but the contents will not have any fraudulent elements.
- Malicious Software Distribution. Disguised messages may contain attachments. In those attached files criminals hide the malware downloader - so it can deliver any nasty thing right to your PC.
- Using the "Man in the middle" method to intercept the personal information of certain individuals and organizations. Such fraud is very effective when you know what the regular mailing the corporation receives looks like.
Types of Email Spoofing
Spoofing e-mail manifests itself differently so that it can be seen in different types. We will consider below a few varieties of Email Spoofing. For sure, there can be other ways to spoof the e-mail, but there we listed the most widely used ones.
Here, the attacker divides the title under a company or organization familiar to you. In [email protected], he does this in the following way:
- Changes the first-level domain to a similar one. For example, [email protected];
- Adds a first-level national domain. For example, [email protected];
- Changes the second-level domain with a character in the name. For example, [email protected];
- Changes the second-level domain associated with the original company. For example, [email protected];
- Leaves the company name as the mailbox name. and the mail is registered in a shared domain. For example, [email protected];
- Substitutes characters, for example "-" changed to "_";
- The capital letter replaces the small, for example, there was "L" and became "l".
Substitution of sender’s name.
At this stage, the sender’s name is forged, but the attacker’s real address remains the same in the From and Reply-to headers. That may work in some mailing clients since they display the sender's address in fine print or do not display it in the letter body. Be picky in your work software!
Changes the value of the From and Reply-to fields.
The user has little chance to notice something wrong, as the attacker approaches this issue very carefully. The hacker can change not only the user name but also the e-mail address bar in the From and Reply-to fields because the SMTP protocol does not authenticate the contents of the header line.
Several ways to Stop Email Spoofing
Every day, intruders develop more ways to make you a victim for their ends. To protect yourself from attacks from fraudsters and hackers, you should know several ways to prevent their activities. Important note - they are most effective when applied simultaneously. Using one of those solutions will likely not change the situation at all.
Deploy an email security gateway
To detect most malware, phishing attacks, and spam, you should use security gateways. They will help you protect your company and block Inbox and Send e-mails that appear suspicious to them or that will not comply with the security policy the enterprise establishes.
Use antimalware software
Good antimalware software will monitor your network that is in and out of it. Antimalware cannot control the messages you receive but will likely stop the connection to a compromised server or a phishing page. Additionally, it will stop any malware that will try to sneak in.
Use encryption to protect emails
Encryption is a great way to protect your email. It guarantees the recipient that the sender is a reliable source. Email encryption is provided by an email signing certificate, thus allowing only the intended recipient to receive the email.
Use email security protocols
Infrastructure security protocols should be used to reduce spam and threats. Businesses can use not only SPF and SMTP but also DKIM identifiable mail for an additional level of security.
Use reverse IP lookups to authenticate senders
To determine the domain name associated with the IP address, you must use a reverse IP address search. It not only checks if the sender is a real user but also checks the e-mail source
Train employees in cyber awareness
Any organization should be careful about training its employees in cybersecurity. This will help avoid security incidents and teach them to recognize suspicious elements and protect themselves from them. Simple educational programs should be carried out all the time. Because attackers constantly develop new methods of their attacks.
Watch out for possible spoofed email addresses
Users should be vigilant when viewing any messages. After all, attackers often repeat their attack tactics. So before you interact with any e-mail address - check it carefully.
Never give out personal information
Establish a policy of not giving your confidential data to anyone. This will protect you from many risks. Do not scatter your passwords from accounts, mail, bank cards, and other similar information.
Avoid strange attachments or unfamiliar links
Pay attention to the links you received via e-mail. Do not rush over them. They may be malicious or even worse. Better check the exact address of the sender by pointing at it with the mouse cursor. If it is not readable or you seem unfamiliar, then it is better not to cross. Sometimes a fraudster can learn from spelling errors or typos.