The Cyber Security Challenge final has launched, tasking 42 amateur white hats to regain control of a naval gun system on board HMS Belfast as a part of a simulated cyber attack by the 'Flag Day Associates' hacktivist group.
The final challenge is the brainchild of experts from GCHQ, the National Crime Agency, Lockheed Martin, Airbus Group, PGI, C3IA and Palo Alto Networks (in partnership with BT).
The finalists will attempt to regain control of a gun system which has been hacked remotely and forced to target London's City Hall.
Contestants will also be required to find similar security holes in a simulated water treatment and manufacturing facility using industry-standard tools, such as the Kali Linux distribution. The winner will be crowned on Friday.
The simulation is the final round in the fifth Cyber Security Challenge, which has seen "thousands" of entrants combat the Flag Day Associates in a variety of fictional situations.
The challenge is designed to help businesses and government departments spot talented individuals and recruit them into cyber security.
Stephanie Daman, CEO of the Cyber Security Challenge, said that many of 2014's finalists now have cyber security jobs.
"Around half of last year's finalists are already in their first cyber security jobs, whilst the majority of the rest are well on their way, taking training courses, accreditations or internships to boost their CVs. There is no reason why all 42 of our finalists today can't follow in their footsteps."
Past winners include 19-year-old student William Shackleton and chemist Stephen Miller.
Cabinet Office minister Francis Maude listed the high turnout and success of participants finding cyber security jobs as proof of the challenge's success.
"Today's competition highlights the very best new cyber security talent as they are challenged by a set of exciting and innovative scenarios developed by GCHQ alongside industry experts," he said.
"Government and business need skilled and talented people to feed the demand for better cyber security in the UK.
"This competition is the biggest and best yet, and events like this play an important role in providing the next generation of cyber professionals."
The challenge final follows a wider push by the UK government to better defend critical infrastructure systems against cyber attacks.
The UK and US governments announced plans to mount a series of simulated cyber war games in January with the intention of bolstering critical infrastructure systems.
The initiatives follow warnings that the cyber threat facing critical infrastructure is growing.
The US Industrial Control Systems Cyber Emergency Response Team revealed on Thursday that US industrial control systems were hit by cyber attacks at least 245 times over a 12-month period.
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