Technology is advancing and internet is expanding to no limits. Cyber war has already began and it started with espionage by different countries. The most critical is NSA spying on the US citizens and foreign networks. Technically cyber war may refer to hacking on server to gain access to information, and exploiting them. Sometimes hackers may attack governmental websites and servers. The most advance and most among of the computer virus was /is the Stuxnet, conspired to be developed by USA and Israel to attack Iran nuclear program. It exploited zero day vulnerability. The malware installed rootKit that affected the nuclear centrifuge spinning rate causing 800-1500 centrifuge damaged. This was first reported by KasperSky LAB. The malware called "Flame" is the product of flame. It is clear that US and Israel will do anything to get information on Iran nuclear program.
There are many examples of such attacks. In 2014, a bunch of government backed elite hackers from North Korea targeted Sony Entertainment, causing massive damage and leaks. This is just the start of dawn of new type of warfare and no a single country will be spared.
