Hacking on a laptop
The European Commission maintains that no data was stolen in the cyberattack iStock

The internet connection of the European Union's legislative body, the European Commission (EC), was disrupted for "several hours" on 24 November (Thursday) after a "large-scale" cyberattack was directed against its computer networks.

The attack, which reportedly started in mid-afternoon, allegedly left staffers unable to work throughout the day. By the evening, as the online assault subsided, the Commission's IT experts sent an email to those impacted blaming the outages on a "denial of service."

This form of cyberattack, also known as a distributed-denial-of-service (DDoS), sends waves of malicious traffic towards a targeted web server with the aim of taking it offline. The European Commission has maintained that no data was stolen in the incident.

"The Commission was the target of a large-scale denial of service attack," a spokesperson confirmed in a statement. "The attack has successfully been stopped with no interruption of service although connections speeds have been affected for a time yesterday."

According to Politico, "millions" of internet requests were sent to the website domain during the event. Additionally, one staffer with knowledge of the event reportedly said: "No one could work this afternoon, since the internet was gone, twice, for several hours."

Apart from sending traffic to the EU's main website, the hackers also targeted its network gateways, Politico said, adding the EU's emergency response team (CERT-EU) was provided details of the threat by the Commission's IT security team.

The identity of the culprits remains unknown at the time of writing. EC spokesperson Margaritis Schinas said: "The attribution of these attacks is difficult because different attackers share and use the same tools. We have no information about the origin of this denial of service."

According to its website, the EC represents the interests of the European Union as a whole. It has headquarters in Brussels, Belgium, and some services also in Luxembourg. The policy-making body has representations in all EU member states and nearly 140 delegations across the globe.

In October, a major DDoS attack occurred in the US and Europe that resulted in a slew of major websites – including Reddit, Netflix and Twitter – going offline. Hackers utilised the so-called Mirai botnet, which is made up of infected internet of things (IoT) devices, to launch the assault.

Most recently, cybersecurity firm Kaspersky Lab warned that DDoS incidents continue to rise in frequency, size and complexity. In a new research paper, it claimed that criminals are increasingly using these attacks as a "smokescreen" to distract attention from hacking attempts.

Kirill Ilganaev, head of DDoS protection at Kaspersky Lab, said: "DDoS prevents a company from carrying on its normal activities by putting either public or internal services on hold. This is obviously a real problem. DDoS can be used [...] as a decoy to distract IT staff from another intrusion taking place through other channels."