Email bombing is a form of internet abuse in which massive volumes of identical emails are sent to a specific email address to affect a computer’s operating system. When the mailbox is flooded with countless unwanted emails, its capacity is exhausted, preventing it from receiving further emails.
This may be done to prevent the victim from receiving or noticing some other important message in their mail. A sluggish system or an inability to send or receive emails can indicate being email-bombed. This happens because the system is already preoccupied with processing countless emails.
Email Bombing and Spamming
There are three methods of email bombing: Mass mailing, List linking, and ZIP bombing. Mass mailing involves sending several duplicate emails to the same address but can be easily detected by spam filters. The second, List linking, involves subscribing the target email address to different email list subscriptions. The user would always receive spam mail from all these subscriptions and would have to manually unsubscribe from each list. Email bombing using ZIP-archived attachments containing millions or billions of characters is known as ZIP bombing. Mail servers checking the mail with anti-virus software would require a more significant amount of processing power, possibly resulting in Denial of Service.
While you cannot eliminate the risk of being email-bombed, there are some preventive & protective measures you can take to reduce its impact. Here are some of them:
1] Use anti-virus software and firewall
You can reduce the chances of being attacked by using anti-virus and configuring a firewall to restrict traffic.
Use email filter applications Email filters are packages that manage unsolicited emails by filtering emails according to the source address. Some of the email filters that are commonly used for Mac OS are:
- SpamSweep
- Spamfence
- POPFile
- Personal AntiSpam X5
Filter package tools for Windows include:
- Email Chomper
- Spam Buster
- Cactus Spam Filter
- SpamKiller
Read: Best free AntiVirus software for Windows
2] Use Proxy Servers
It is challenging to spam and filter each and every email bomb coming from different IP addresses. Such a situation could be mitigated using proxy servers. A proxy server is a computer to which all other computers in a particular network are connected.
The proxy server has specific rules for filtering the messages it receives that request information and resources from the computers connected to it. This helps filter malicious requests and messages originating from suspicious IP addresses before they reach the proxy server’s clients.
3] Using Simple Mail Transfer Protocol (SMTP)
Denial-of-service attacks can also be mitigated using SMTP, which authenticates message exchange over Internet protocols. The clients access their mailbox using Post Office Protocol (POP) or the Internet Message Access Protocol (IMAP).
Through SMTP, the Mail Submission Agent transfers mail or information to the Mail Transfer Agent (MTA). Upon connecting to SMTP, the MTA analyses the mail exchange record and the sender’s IP address and rejects the message if they are found to be suspicious. Security mechanisms, such as authentication and negotiation, are performed during data exchange.
It is essential that you identify the source of the email bombs, and once you have identified it, you need to configure your router or firewall and prevent incoming packets from that address.
Read next: Benefits of Masking Email Address.
