Techwatch is back online following a sustained denial of service attack that left the digital TV news site unavailable for two days earlier this week.
The botnet-powered assault was accompanied by blackmail demands posted on the site's forum through compromised zombie machines. These threatening messages claimed the site was being carpetbombed with spurious traffic generated through a 9,000 strong botnet of compromised machines.
Techwatch was able to restore the site to normal after applying advanced traffic filters.
Brian Turner, Executive editor of Techwatch, told El Reg that the assault is evidence that denial of service extortion attacks are a problem not just for traditional targets such as bookmakers but for mainstream web businesses.
Techwatch was hit by a 446Mbps distributed denial of service attack on Tuesday, 27 January which rose to 2Gbps on Wednesday. The deluge of spurious (SYNflood) requests left the site unable to cope with genuine visitors.
"Techwatch normally handles between 15,000-25,000 uniques per day without problem, but there's little chance of us staying online with 2Gbps traffic," Turner explained.
The site was restored to normal service on Thursday afternoon. Turner said his experiences with Techwatch should act as a warning for other web businesses who face dangers more severe than defacement by script kiddies, the more traditional form of threat.
"Anyone with a popular website is at risk of it being hacked - this time for commercial purposes - not least to insert hidden links to porn, pills and pharmaceuticals sites," Turner explained. "The danger is, the recent Techwatch DDoS could be a part of an increasing trend where everyday webmasters could find themselves victims of a new form of protection racket - blackmailed into paying to stop their sites being taken down by a SYNflood."
Webadmins can add procedures on how to deal with such an attack as part of their disaster recovery planning, he added. "Ensure you know which are your most important IPs for delivering customers. Web crawlers, newsbots, and anything similar which act as main traffic channels to your website. This way, if you do have to aggressively block IP ranges, you can whitelist these.
"Website admins should also keep an eye on their server logs to spot early signs of trouble."
The assault on Techwatch follows a denial of service attack on hardware enthusiast site Overclockers UK. OcUK is offering a £10,000 ($13,380) reward for information that results in the arrest and convictions of the perpetrators of the attack, the motives for which remain unclear. ®