Security experts have reacted angrily to a report on Sky News this week alleging that the Stuxnet worm is now being traded on the black market and could be used by terrorists to launch attacks on the UK’s critical infrastructure.

The report quotes a “senior IT security source” as saying that there is “hard evidence that the virus is in the hands of the bad guys”.

Sky News also quotes UK government IT security consultant Will Gilpin as saying that the worm could shut down the emergency 999 service, along with hospital systems, power stations and “the transport network across the UK” .

However, David Harley, a senior research fellow at anti-virus firm Eset, branded the report “a sorry dishrag of a story”, and said that many supposed outcomes of the worm being sold on the black market are greatly exaggerated.

Harley explained in a blog post that it might be possible to shut down some hospital systems “at a (biiiiiiiig) stretch”, in the “unlikely event that they use equipment supplied from Tehran or Finland in certain therapeutic contexts”.

The researcher suggested that the Sky News report had been based on a “garbled, super-hyped interpretation” of a story emerging earlier this week that the source code for the yet-unpatched Windows Task Scheduler, which is just one of the four vulnerabilities used in the Stuxnet attacks, can now be bought online.

Paul Ducklin, head of technology for Asia Pacific at Sophos, also picked holes in the sources used by Sky News, claiming that they were “hiding behind the ‘if I tell you, I’ll have to kill you’ cop out”.

“We don’t need yet more speculation about Stuxnet when we already face a determined and extensive enemy in the form of cyber criminals,” he said in a blog post.

“They are routinely stealing our credentials, plundering our bank accounts, raiding our retirement funds, subverting our payment systems and even selling our houses from under our feet.”

Ducklin added that inflammatory stories such as this make cyber crime sound like a second-rate problem.

“Yet it is the sort of rampant and general cyber criminality I mention above which is, in my opinion, significantly more likely to undermine the economic stability of, and thus the quality of life in, many developed countries,” he said.