SINGAPORE - The failure of airline navigation systems leading to an aircraft collision and the jamming of mobile signals resulting in loss of communication may seem like scenes from an action movie, but these threats - arising when satellite systems are hacked - are closer to reality than one might think, experts say.

"We see that hackers have more efficient tools... (and) the satellite system is a very attractive target for hackers because a lot of our activities are now based on services provided by satellites," said Mr Franck Perrin, head of cyber-security, platform and infrastructure for satellite manufacturer Thales Alenia Space.

He said many components in satellites have now been replaced with software, thereby allowing the space platforms to become more connected to ground infrastructure and opening up more ways for them to be accessed through such systems.

Mr Perrin was addressing journalists from around the world at Thales Media Day, organised by French multinational firm Thales in Paris last month.

Mr Massimo Mercati, head of the European Space Agency's Security Office, said at the same event that all it takes is a lone hacker breaking into the ground systems of the satellite network or a criminal organisation with resources to attack the satellites directly.

The latest known attack on a satellite network took place on Feb 24 and came as Russia invaded Ukraine.

The hack took down the satellite broadband services of tens of thousands of households across Europe, said Internet service provider Viasat, which owns the satellite.

The hacker, who was not identified in Viasat's report, had exploited a misconfiguration in a virtual private networking device, which is part of a ground system, to gain remote access to the company's network connecting its KA-SAT satellite and customers' modems.

The intruder then sent commands to numerous modems, which overwrote key data in the devices' memory storage and disabled them. But Viasat said the satellite was not compromised.

The European Union as well as countries such as the United States and the Britain have blamed Russia for the cyber attack, Reuters reported.

At the event in Paris, Thales business development manager Silvia Diana said the main target of cyber attacks on satellite networks are ground systems.

If successful, the intruders can wreak havoc by sending wrong commands or uploading malicious software to various components of the compromised network.

These attacks can affect services such as TV broadcast, Internet connectivity and navigation systems, as well as corrupt data sent over networks, including information relating to banking, military operations and scientific studies, she said.

Mr Perrin noted that there has been no known cases of satellites being hacked directly.

But this does not mean such a cyber attack will not happen, he added.

Mr Mercati said all it takes is a criminal organisation with resources and the technology to do so.

Similar warnings on the hacking of satellite communications were sounded as early as 2018 when researchers at a Black Hat conference in Las Vegas said such threats to ships, planes and military were no longer just a theory.

Specifically, freelance security researcher Ruben Santamarta had warned that various popular satellite communication systems are vulnerable to cyber attacks due to weaknesses in their security measures, such as backdoors that hackers can use to easily access the systems.

"The consequences of these vulnerabilities are shocking," he said in a 2018 report by British media outlet The Guardian.

"Essentially, the theoretical cases I developed four years ago are no longer theoretical."

Mr Santamarta, who was working for information security firm IOActive at the time, said these attacks work by accessing and taking control of a satellite antenna on the ground, allowing the hacker to intercept or disrupt communications - such as eavesdrop on e-mails - or even launch further hacking attacks on connected devices.

The hackers would also be able to pinpoint the location of the satellite antenna, which could compromise the location of military forces or bases using it.

The researcher also said the antenna may be used to launch a "high intensity radio frequency attack", which can cause damage to electrical systems.

"It's pretty much the same principle behind the microwave oven," he added.