A total of 63 leaks of defense industry data occurred between 2021 and September this year. Most of the leaked material involved defense science and technology, and because recent cases have been concentrated in cyber breaches, critics say a full review of the security management system for protecting defense technology is urgently needed.
According to data submitted by the Defense Acquisition Program Administration (DAPA) and released on the 13th by Yoo Yong-won, a People Power Party lawmaker on the National Assembly's National Defense Committee, defense-related data leaks totaled 49 over the past five years: eight in 2021, three in 2022, five in 2023, 17 in 2024 and 16 in 2025. Another 14 cases were confirmed through September this year, bringing the cumulative total to 63.
Of those, 47 cases — about 75% of the total — were concentrated between 2024 and September this year. Among them, 41 stemmed from cyber breaches such as hacking, while the remaining six were traced to personnel, including current and former employees who removed work-related material without authorization.
Cyberattack attempts targeting DAPA have also continued unabated. A total of 30,811 attempts were confirmed from 2021 through Oct. 1 this year. Attempts to collect system information were the most common, exceeding 3,000 each year, while system access attempts — including unauthorized logins and access to files inside servers — jumped roughly 15-fold to 868 this year from 57 last year.
Hacking incidents suspected of being carried out by North Korea or linked to the country were also found. DAPA said three such incidents occurred at general defense industry subcontractors — two in 2024 and one in 2025. Files were actually leaked in two of the cases, while the third remains under investigation.
DAPA says, however, that there are limits to identifying the perpetrators. "Because attackers combine tactics such as spoofing IP addresses and routing through overseas bases, there are limits to determining the actual origin of an attack or confirming whether the hacking passed through a third country," the agency said.
Yoo said it is a serious problem that even data on defense science and technology directly tied to national security is being leaked. "Once defense technology is leaked, it is difficult to undo, so the state of defense technology protection and the security management system must be thoroughly reviewed," he said.
He added that an amendment to the Defense Industry Technology Protection Act, which passed the National Assembly plenary session in May, was also intended to toughen penalties for defense technology leak crimes. "Protecting core national technology is directly linked to national security, so DAPA must strengthen oversight of defense technology security and come up with effective measures to block technology leaks in advance," he said.