Tether confirms DDOS attack on tether.io

Tether CTO, Paolo Ardoino, has confirmed that the Tether website, tether.io, is currently suffering a DDOS attack. The number of requests for the website increased from 2,000 to 8,000,000 every five minutes early on Saturday morning, June 18. The chart below showcases the increase in requests.

Ardoino confirmed that the “attack is now mitigated,” but they are “leaving the ‘I’m under attack mode’ enabled” to mitigate further risk. According to the Tether CTO, the additional security move “won’t affect the ability of redeeming,” according to the Tether CTO.

Under attack mode

“I’m under attack mode” is a feature of Cloudflare’s DNS management service that protects websites from DDOS attacks by forcing users to complete an additional step to access the website. For human users viewing the website through a standard web browser, this results in a few-second delay while the browser completes a javascript challenge.

If the browser cannot complete the challenge, then the user may be required to complete a captcha to get to the website. However, DDOS attacks are often conducted using remote servers making requests on the website from outside of a browser.

These methods will fail the challenge request and thus get kicked before even reaching the server. Here, Cloudflare handles all the excess demand leaving the website free to perform tasks as usual. Ardoino also confirmed that the reason for the issue was that “it takes a bit of time for the auto-scale to adjust.” In this, he refers to the ability of the server behind the website to scale up resources to cope with the unexpected increase in demand.

Earlier on Saturday, Paolo tweeted, “It will be a long weekend,” but it is unlikely he expected it to be due to an attack on Tether’s website.