Despite an August patch, Russian and Chinese state-backed hackers are using a vulnerability in the popular software to carry out espionage.

Russian hacking operations in support of intelligence gathering and information operations related to the war show no signs of slowing down.

The operations are just the latest example of the proliferation of sophisticated spyware among private vendors, Google says.

Google's report on the Ukraine war shows how Russia executed information operations and hacking campaigns to gain an advantage in cyberspace.

The notorious hacking group used the Halloween tragedy that killed more than 150 people to trick South Koreans into downloading malware.

Google says it has deployed patches for zero-day vulnerabilities that a Spanish tech company may have used to develop spyware.

Security researchers linked the program to the so-called Charming Kitty Iranian hacker group known to carry out intelligence operations.

Spyware such as NSO Group-produced Pegasus is proliferating quickly and poses a threat to privacy and national security, experts said.

The campaign is just the latest example of the increasingly sophisticated world of private zero-day exploit development, researchers said.