Personal information leaks occurred one after another through mid-October 2026, with more than 165 million leaked records reported. Cases involving Sourcenext and H2O ID, among others, were reported, prompting calls for heightened government vigilance and a review of zero-trust measures, while security-related stocks showed movement.
As of mid-October 2026, the number of personal records reportedly leaked through unauthorized access had exceeded 165 million. Specifically, Sourcenext disclosed a leak of approximately 22.51 million records on 15 October, and H2O Retailing disclosed a leak of approximately 1.26 million records on 19 October. On 8 October, the government held a meeting of the relevant ministries and agencies and regarded the situation as extremely urgent. In addition, reports emerged that GSS, a government-affiliated platform, may have been compromised through a VPN vulnerability and administrator accounts, highlighting risks that cannot be prevented through external defenses alone.
Scepticism grew over the effectiveness of perimeter defenses centred on zero trust, and calls were made to strengthen measures including identity management, post-incident monitoring and data protection. Against this backdrop, buying interest in security-related stocks increased, and news concerning personal information leaks began to affect stock market trends.
Based on public information, the article selected 20 stocks as candidates for the next focus from three perspectives. These include underperforming stocks among major systems integrators and trading-related companies, first-wave stocks that rebounded after plunging, and peripheral areas related to internal fraud and authentication management. The article explicitly states that major stocks were deliberately excluded in order to identify the next focus.
In terms of stock market movements, a total of 10 stocks, including Broadband Security and Cyber Security Cloud, reached their daily upper price limits simultaneously on 6 October. From the 16th to the 19th, SecureVeil, Azgent and Terilogy Holdings recorded consecutive limit-up closes. On the other hand, SecureVeil plunged on the 20th from an intraday high, at one point trading approximately ¥300 below the previous day's close.