Email remains the favourite tool of cybercriminals because it reaches people directly and costs almost nothing to send. Understanding the threats is the first step to stopping them. Here are the twenty that matter most to businesses today, with the defence for each.
1. Phishing
Messages that pretend to come from a bank, courier or your own IT team, aiming to steal passwords or plant malware. Modern phishing is polished and often free of spelling mistakes.
Defence: AI-driven filtering that analyses intent, plus staff awareness training.
2. Spear phishing
Phishing aimed at one person, built from details found on LinkedIn or your website. It references real projects, suppliers and colleagues.
Defence: Behavioural analysis that flags unusual senders and requests.
3. Whaling
Spear phishing aimed at senior executives, whose access and authority make them high-value targets.
Defence: Extra protection and training for leadership accounts, with two-factor authentication enforced.
4. Business email compromise (BEC)
Criminals impersonate an executive or supplier to request urgent payments. These emails often contain no links or attachments, so basic filters miss them.
Defence: AI impersonation detection and a call-back rule for every payment request.
5. Viruses and malware
Infected attachments and links install spyware, keyloggers or remote access tools.
Defence: Server-side virus scanning before mail reaches the inbox.
6. Ransomware
Malware that encrypts files and demands payment. Email is one of its most common entry points.
Defence: Layered antivirus and antispam, plus tested offline backups.
7. Account takeover
Attackers log in with a stolen password and send fraud from a trusted internal address.
Defence: Two-factor authentication on every mailbox.
8. Email spoofing
Forged “From” addresses make a message appear to come from your own domain or a trusted partner.
Defence: SPF, DKIM and DMARC authentication on your domain.
9. Look-alike domains
Domains that differ by one character, such as yourcompamy.com, used to fool busy readers.
Defence: AI filtering that detects domain impersonation, and staff who check full addresses.
10. Malicious links and redirects
Links that pass through several harmless-looking hops before landing on a fake login page or malware download.
Defence: Link analysis at the server before delivery.
11. QR code phishing (quishing)
A QR code in an email sends the reader, usually on a phone, to a credential-stealing site, bypassing link scanners.
Defence: Training staff never to scan QR codes from unexpected emails, and filtering that inspects image-based lures.
12. Thread hijacking
Attackers reply inside a genuine email conversation taken from a compromised mailbox, making a malicious file look expected.
Defence: Two-factor authentication to prevent the initial compromise, and AI that spots sudden changes in a thread.
13. Invoice and supplier fraud
A real or impersonated supplier “updates” bank details so the next payment goes to criminals.
Defence: Verify every bank-detail change by phone using a number already on file.
14. AI-generated phishing
Criminals now use AI tools to write fluent, personalised scams at scale in any language.
Defence: AI-driven antispam that judges behaviour and patterns, not just grammar.
15. Brute-force and password spraying
Automated tools try common passwords against many accounts until one works.
Defence: Strong password policies, two-factor authentication and country-based login restrictions.
16. Logins from high-risk countries
Many attacks originate from regions where your company has no staff or customers.
Defence: Country-based login restrictions that block sign-ins from outside approved countries.
17. Malicious forwarding rules
After taking over a mailbox, attackers set hidden rules that silently copy mail to an outside address.
Defence: Admin monitoring of forwarding rules and fast response to compromised accounts.
18. Accidental data leakage
Sensitive files sent to the wrong person, or confidential data shared without protection.
Defence: Clear email policies, staff training and careful use of autocomplete.
19. Email bombing
Thousands of sign-up and spam messages flood an inbox, often to hide a fraud alert or password reset in the noise.
Defence: Intelligent filtering and a support team that can respond quickly.
20. Spam overload
A flooded inbox wastes time and hides dangerous messages among the noise.
Defence: An antispam engine that learns what your users actually want to receive.
Bringing it together
No single tool stops all twenty threats. The strongest protection comes from layers working together: AI filtering, virus scanning, strong authentication, login controls, domain authentication and informed staff.
How Smardove defends your business
Smardove combines an AI-driven antispam engine powered by SpamFoo, virus scanning, two-factor authentication and country-based login restrictions in one hosted email service. Its AI classification engine also sorts legitimate mail into clear categories, so real threats stand out and important messages never get lost.
| Protect your team from today’s email threats. Speak to Smardove about secure hosted email for your organisation. |
