The website of Donald Trump's new cyber-guru Rudy Giuliani has a low security rating and is extremely vulnerable to hackers, tech experts claims.

In announcing Giuliani's new advisory role in the Trump administration on Thursday, the president-elect's transition team drew on his 16 years experience providing security solutions in the private sector.

But tech experts were quick to point out on Twitter that Giuliani - a former New York City Mayor - had failed to safeguard his own company's website with adequate security measures.

Rudy Giuliani was revealed on Thursday as Donald Trump's new cyber-guru, with the transition team citing his 16 years experience providing security solutions in the private sector

His website giulianisecurity.com, which crashed several times on Thursday, is run on an outdated version of Joomla! - a freely available content management system.

The version of the CMS Giuliani is using for his website is about four years old, which features more than a dozen vulnerabilities.

The flaws were pointed out by on social media by numerous renowned hackers including The Jester and Phobos Group founder Dan Tentler.

'Giuliansecurity.com is currently down. Unclear if Trumps cybersecurity pick killed it out of shame or sheer weight of twitter laughing,' The Jester tweeted.

Jim Troutman wrote: 'So, the overall security of the giuliansecurity.com website is awful. A default cloned ssh key!? Seen teenagers build more secure servers.'

Michael Fienen, a CMS developer, was quick to ridicule Giuliani by listing about 10 problems he could see with the website.

'To recap on Rudy Giuliani leading the nation's cybersecurity efforts, here are the Cliff Notes on Giuliani Security,' he wrote.

'Oh yeah, I totally trust this guy to put together a top notch teach to protect us from hackers.'

Tech experts were quick to point out on Twitter that Giuliani had failed to safeguard his own company's website giulianisecurity.com with adequate security measures

His website giulianisecurity.com, which crashed several times on Thursday, is run on an outdated version of Joomla! - a freely available content management system

Giuliani's website also received an F security rating from SSL lab grade

Among the issues is an exposed CMS login, which makes it easier for a hacker to target the website.

Giuliani's website also received an F security rating in a server testing report from Qualys SSL lab.

Revelations about his website come just hours after it was announced Giuliani will lead cyber security efforts for team Trump.

While he will stay in the private sector, Giuliani told Fox & Friends that he would play an advisory role in the new administration.

'I’ll coordinate the whole thing, I’ll get the people in, make sure the meeting takes place, make sure they get the information from the private sector,' Giuliani said.

Many expected Giuliani to be tapped for a cabinet job because of his political support for the billionaire. But when he was passed over for secretary of state, with Trump choosing Exxon/Mobil CEO Rex Tillerson instead, the former New York City mayor decided to stay outside the administration.

His website giulianisecurity.com is run on an outdated version of Joomla! - a freely available content management system

'He offered me some cabinet positions, which I'm very, very thankful for,' Giuliani said on Fox & Friends last month, noting that secretary of state was not among them. 'It just didn't work out in terms of my private life.'

This job, however, allows Giuliani to straddle both worlds, as he'll be doing work for Trump, but also remain outside of government.

'Mr. Giuliani was asked to initiate this process because of his long and very successful government career in law enforcement and his now sixteen years of work providing security solutions in the private sector,' the transition's release explained.

The idea is that Giuliani will bring corporate leaders together on a regular basis to discuss cyber security, as the transition team noted that 'cyber intrusion is the fastest growing crime in the United states and much of the world.'

Giuliani said he believed the answers to this problem would be found in the private sector and by a meeting of the minds.

Former New York City Mayor Rudy Giuliani appeared on Fox & Friends this morning to announce he's been charged with heading a cyber security initiative for the president-elect

Rudy Giuliani (left) will bring together private sector leaders to discuss how to thwart cyber threats as part of his new role

'It’s like with cancer. There is cancer research going on all over place, you’d almost wish they’d all get together in one room, and maybe we’d find a cure,' Giuliani said.

Vice President Joe Biden's cancer moonshot work prescribes to this theory.

At Trump Tower today, Giuliani stopped to talk to reporters and explained that while modern technology has really evolved over the past 20 years, 'our ability to defend that has lagged behind.'

On Fox & Friends he used football, and one of the local teams, the New York Giants, to explain his new role.

'Our offense is here and our defense is here, we've got to do what the Giants did last year, we've got to invest in our defense so we can catch up,' the former New York City mayor explained.

'Maybe we won't make a super Bowl in one year, but we may be there next year,' he said.