Phishing. It seems you can’t read an article on cybersecurity without it coming up. That’s because phishing is still the number one delivery vehicle for cyberattacks.

A cybercriminal may want to steal employee login credentials. Or wish to launch a ransomware attack for a payout. Or possibly plant spyware to steal sensitive info. Sending a phishing email can do them all

80% of surveyed security professionals say that phishing campaigns have significantly increased post-pandemic.

Phishing not only continues to work, but it’s also increasing in volume due to the move to remote teams. Many employees are now working from home. They don’t have the same network protections they had when working at the office.

Why has phishing continued to work so well after all these years? Aren’t people finally learning what phishing looks like?

It’s true that people are generally more aware of phishing emails and how to spot them than a decade ago. But it’s also true that these emails are becoming harder to spot as scammers evolve their tactics.

One of the newest tactics is particularly hard to detect. It is the reply-chain phishing attack.

What is a Reply-Chain Phishing Attack?

Just about everyone is familiar with reply chains in email. An email is copied to one or more people, one replies, and that reply sits at the bottom of the new message. Then another person chimes in on the conversation, replying to the same email.

Soon, you have a chain of email replies on a particular topic. It lists each reply one under the other so everyone can follow the conversation.

You don’t expect a phishing email tucked inside that ongoing email conversation. Most people are expecting phishing to come in as a new message, not a message included in an ongoing reply chain.

The reply-chain phishing attack is particularly insidious because it does exactly that. It inserts a convincing phishing email in the ongoing thread of an email reply chain.