It looks like the joke was on Microsoft on 1 April, with 88 of a reported 103 defacements taking place on websites based on Windows NT servers, mostly combined with some version of IIS.
Various big-name UK sites were hit as part of a mass April Fool hack attack, including Burger King, which has only just recovered from a hacker grilling a month ago, HSBC, Dunhill and BT.
Hacking group World of Hell, which defaced the BT.com page, also left a rant about the delays dogging the rollout of ADSL in the UK, and coined an amusing alternative phrase for the acronym: Always Delayed Slightly Longer.
Other major sites hit were the US Army and Navy training sites and the American Society for the Prevention of Cruelty to Animals.
The idea behind the attacks seemed to be to go for vulnerable boxes because it was possible to breach their security. Most of the groups responsible posted up messages claiming that no other files had been touched and that they had only modified the Index page. Some even pointed system administrators towards the download locations of fixes for the glitch that let them hack in.
But some companies are obviously not learning from such incidents. Some 14 of the sites affected this time had been hit before, and most of these had even been compromised over the last month.
This would appear to indicate that systems administrators are not securing their systems properly even after an intruder has broken in.
But Windows 2000 product manager, Mark Tennant, said a high number of Windows NT boxes were compromised simply because it was a popular platform. Acknowledging that many of the hacks were carried out using known vulnerabilities, he said: "It's a case of applying best practice to security and keeping patches up to date."
Tennant explained that tools were available to remove the burden from network managers and help them keep on top of security fixes. He added that there was a significant drop in the number of Windows 2000 web servers being compromised in relation to the number of NT 4 boxes broken into.
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