A new report says hackers could wreak havoc by interfering with space-based communications and navigation services that NATO armies rely on.

The threats: The study, published by the UK’s Royal Institute of International Affairs, says that military satellites face the threat of hackers using malicious code to jam battlefield communications or disrupt automated missile-defense systems. Attackers can also create fake GPS signals from satellites. Known as “spoofing,” this could be used to surreptitiously redirect everything from planes to ships and ground forces.

Security researchers have already highlighted the vulnerabilities associated with communications satellites. Hacking satellites could be a far more effective way of compromising an enemy than simply blowing them up.

Satellite dependency: During the US-led invasion of Iraq in 2003, just over two thirds of US munitions were guided via “space-based means” says the report—up from just a tenth during the first Gulf War in 1990-’91. This “critical dependency on space” makes cyber vulnerabilities all the more concerning.

Plugging the holes: The think tank has come up with a list of steps NATO countries should take to improve satellite security. These include making sure all ground control systems are properly protected with updated software and access controls, as well as ensuring greater interoperability between different countries’ satellite so that if one group is hacked, troops can rely on other satellites for backup.

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