Every WhatsApp user has probably received a spam message from an unknown person. The messaging service has now found a new way to combat this WhatsApp spam.
WhatsApp spam and encryption: a tricky balance
Preventing the spread of spam messages is an important task for any messaging service. Since WhatsApp uses end-to-end encryption to protect messages, this has become a lot more difficult. After all, WhatsApp itself can no longer view messages with this form of encryption. Good news for your privacy, but also for spammers who can be more difficult to catch as a result.
WhatsApp employee Matt Jones explains at the USENIX Enigma conference how they solved this problem. A special team set to work to detect WhatsApp spam without looking at the content of the messages themselves. Instead, Whatsapp analyzes a user’s behavior to determine whether or not they are sending spam messages.
This approach seems to work, as Jones says the number of WhatsApp spam messages has dropped by 75 percent since the technology was introduced. Jones does not want to say exactly how WhatsApp achieved this impressive percentage, although he does have a tip of the veil.
For example, the service looks at the number of messages someone sends per minute. If this number is noticeably far above the average, the account is immediately suspect. By then comparing the network and provider the person is using against a list of known spam addresses, the service further determines whether it is a spam account.
On the verge of privacy
The location of the user also plays a role. If someone with a Canadian account suddenly sends messages regularly via Thailand, alarm bells will ring. Because WhatsApp never looks at the content of messages during these steps, the system can of course be wrong. Therefore, users can appeal to get the account active again.
Although the messaging service does not read what you say, the app does use all kinds of other information from you as a user. Jones therefore emphasizes that WhatsApp does this as little as possible to guarantee the privacy of the user.