igor - Fotolia
Hacking group Lizard Squad claimed responsibility for the attack in revenge for the arrest of six teenage hackers in five UK locations.
The arrests were part of Operation Vivarium, which was co-ordinated by the NCA and involved officers from various police forces and Regional Organised Crime Units (ROCUs).
The six were arrested on suspicion of using the Lizard Squad’s Lizard Stresser DDoS attack tool to target a national newspaper, a school and online gaming companies and retailers.
The NCA said in a statement that its site is an attractive target and attacks on it “are a fact of life”. It added that the latest attack was not a security breach and did not affect its “operational capability”.
The NCA said that it had a duty to balance the value of keeping its website accessible with the cost of doing so.
“The measures we have in place mean our site is generally up and running again in 30 minutes, though occasionally it can take longer,” the statement said.
The digital world has become an increasingly hostile environment, according to Wieland Alge, vice-president and general manager for Europe at Barracuda Networks.
“The more organisations that rely on a digital environment, the more we see a shift in criminal activities towards digital methods,” he said.
According to Alge, some organisations either think they have time to wait until they become a target or they believe they can weather the storm.
“Organisations need to be prepared. Whoever does not wear a raincoat and have an umbrella to hand these days will get wet,” he said.
The aim of the NCA-led Operation Vivarium was to crack down on DDoS attacks, as well as raise awareness on the issue.
DDoS attacks typically flood web servers or websites with requests, leaving them inaccessible to users.
In a DDoS attack on popular UK parenting site Mumsnet, the site received about 17,000 requests per second, compared with its normal hit rate of 50 to 100 requests per second.
As part of the law enforcement operation, the NCA said police officers are also visiting around 50 addresses linked to individuals registered on the Lizard Stresser website.
The visits also form part of the NCA’s wider work to address younger people at risk of entering into serious forms of cyber crime.
Those receiving visits will be told DDoS attacks are illegal, can prevent individuals from accessing vital online services and can cause significant financial and reputational damage to businesses.
They will also be informed that committing cyber crime can result in severe restrictions on their freedom, access to the internet, digital devices and future career prospects.
For the past nine months, DDoS attacks have doubled compared with the equivalent periods the year before, according to the latest Akamai security report.
While attackers favoured less powerful but longer duration attacks during the second quarter of 2015, the number of dangerous “mega attacks” continued to increase, said the Akamai Q2 2015 State of the Internet Security Report.
Read more about DDoS attacks
- While extremely large DDoS attacks grab the headlines, it is the increasing size of the average attack that is affecting enterprises, warns Arbor Networks.
- Complacency about DDoS attacks is putting businesses at risk, a survey has revealed.
- DDoS attacks could expose 40% of businesses to losses of £100,000 or more an hour at peak times.
- All indications show DDoS attacks are increasing in variety, number and size.