According to Cointelegraph, internet infrastructure company Cloudflare has reported that over 5% of all emails sent globally contain malicious content. The firm analyzed global email traffic over the past year and found that 5.6% of it was malicious, equating to more than one in every twenty emails containing harmful content. Notably, in November, this figure surged to nearly one in ten emails, almost doubling the annual average.
Cloudflare's 2025 year-in-review report highlights the dangers of malicious emails, which can lead to credential theft, data breaches, or financial loss. This is particularly concerning for crypto investors, as phishing attacks targeting traders, investors, and executives have become more sophisticated and frequent. Once a victim falls for a phishing link or sends cryptocurrency to a scammer, recovery is often impossible. In November, malicious emails reached 9.7%, with deceptive links being the most prevalent threat category, accounting for 52% of these emails.
Identity deception was the second most common threat, rising to 38% from 35% in 2024. Attackers often impersonate trusted individuals using spoofed domains, similar-looking domains, or display name tricks. Cloudflare identified the most abused top-level domain (TLD) extension as ".christmas," with 92.7% of emails from this domain being malicious and 7.1% being spam. Other frequently abused domains include ".lol," ".forum," ".help," ".best," and ".click."
Earlier this year, cybersecurity firm Barracuda analyzed 670 million emails, finding that email remains the most common attack vector for cyber threats. Malicious attachments and links are often used to distribute malware, launch phishing campaigns, and exploit vulnerabilities. They reported that one in four emails were unwanted spam, a quarter of all HTML attachments were malicious, and 12% of malicious PDF attachments were Bitcoin scams. In November, Hornet Security noted that email was a "consistent delivery vector" for cyberattacks in 2025, with malware-laden emails increasing by 131% year-over-year.
