Spy agencies of South Korea and Britain on Thursday issued a joint cyber security warning against North Korea's hacking attempts targeting software supply chains.

The joint alert was issued by the National Cyber Security Center under South Korea's National Intelligence Service (NIS) and its British counterpart under the Government Communications Headquarters.

The NIS said that the two nations officially identified cases of the North’s hacking groups’ attacks through cooperation between their cyber security organizations and technology cooperation between information security companies. 

The NIS said that the identified hacking incidents include a “watering hole attack” on MagicLine4NX, a certificate program used by tens of millions of people in South Korea. A watering hole attack targets a specific group of users by infecting websites that they are likely to visit.

Another case involved the infiltration of the 3CX’s desktop application software, used by around 600-thousand companies and institutions worldwide, including those in the aerospace and medical industries. North Korean hackers ingeniously planted malicious code in the 3CX installation program to extract user information.

The spy agencies of the two nations advised users to update their antivirus software to ensure protection against such breaches. 

The joint warning came shortly after a recent summit agreement to enhance cybersecurity cooperation between South Korean President Yoon Suk Yeol and British Prime Minister Rishi Sunak.