Spam is defined as irrelevant or unsolicited messages sent to a large number of Internet users, for illegitimate advertising, and other activities such as phishing, and spreading malware.
Spam is a boon for instantly marketing a product or service to thousands of Internet users with an email id. It is the cheapest way of commercial marketing. Spam is also called as junk email or electronic spam.
Email spam can be used for legitimate purposes such as sharing or sending a message to a large group of people. However, its illegitimate uses obliterate its legitimate useful purposes. Like many useful utilities now being predominantly used for illegitimate purposes, the usefulness of sending a mail to multiple users is being used for sending spam.
Spamming is used for sending fraud mail, phishing campaigns, identity theft, and for sending malicious executable file attachments, links to malicious websites and phishing websites for illegitimate activities.
People/organizations who engage in the activity of sending spam mails are called as spammers.
A botnet is defined as a network of Internet-connected devices under the control of a botmaster. A botmaster remotely controls bot networks. Each device that is part of the bot network could run multiple bots. Skilled botmasters remotely control botnets that run up to millions of devices. Botmasters typically target IoT devices with poor security and recruit them as part of bot networks. Favored targets are devices such as security cameras and digital video recorders.
Why is Spam Harmful
Spam is a catastrophe as around 90% of email messages are spam email. Spam is repetitive and fills up mail-boxes. It wastes bandwidth, affects server performance, and consumes hard disk space and memory. Spam is present everywhere and is unavoidable. Spam affects employee productivity as it induces the person to check the mail for valid reasons. Considerable, valuable time is spent. Spam mails could be dangerous as opening spam mails, clicking on any links or downloading any attachments could infect device with dangerous malware.
The Value of your Email Addresses
Getting your inbox filled with spam would demonstrate the value of your email id. Openly sharing email addresses has its disadvantages. Scrupulous entities could target your id with spam email. Email addresses are harvested from customer lists, address books, contact lists, social media, websites, and chatrooms. On Android devices some apps request access to the address book (contacts) even if it not necessary for them. Some apps surreptitiously collect the details on the contact list on the Android device. Android users are warned to check for the necessity of permissions requested by apps.
Protection from Spam
Email service providers provide protection against spam through filtration mechanisms. Most anti-spam tools utilize signature-based detection to block messages based on malicious attachments, sender reputation, user reports, and types of files. Emails are scanned for malicious attachments and executables, and scripts are blocked.
Effect of Spam Mail on Corporate Sector
Spam affects performance of network, machines and productivity of users. Every minute spent on spam email to view or even delete is lost productivity. Signature-based methods to block spam do serve some purpose. However, they do not provide protection against "unknown" malicious files. Some emails are made to appear as if they originated from the administrator asking the user to immediately change the password. The credentials get captured when the user changes the password.
The general precautionary measure is that every user is warned not to click on links or open attachments in emails from unknown sources. While this method provides protection, it blocks even legitimate emails - false positives.
Anti-spam gateway tools are used by corporates to block spam. However, these techniques are not very effective against unknown files as they are signature-based detection methods.
Threat of Unknown Files
Avoiding opening of attachments in emails from unknown sources is a prudent measure, but it could be valuable business proposals from a new client. Not opening would mean loss of business. Effective tools such as the Comodo Antispam Gateway (ASG) allow users to open all attachments. Using the cloud-based Valkyrie system, the ASG scores email attachments as good, bad, or unknown.
Comodo Antispam Gateway (ASG) places all unknown files in containment for further analysis. Meanwhile, users can access, open, and execute the unknown email-borne files without any fear of getting infected due to the unique containment system.