Hackers lurked in Treasury OCC’s systems since June 2023 breach

Unknown attackers who breached the Treasury's Office of the Comptroller of the Currency (OCC) in June 2023 gained access to over 150,000 emails, according to anonymous sources familiar with the matter. The OCC is an independent bureau of the U.S. Department of the Treasury that oversees banks and federal savings associations and ensures they comply with applicable laws and regulations, treat customers fairly, and provide fair access to financial services. As Bloomberg first reported, the threat actors gained the ability to monitor employees' emails after breaking into an email system administrator's account, as OCC disclosed in February 2025. At the time, it reported the attack to the U.S. Cybersecurity and Infrastructure Security Agency as a "cybersecurity incident" involving its email system and multiple email accounts, with no impact on the financial sector. "The Office of the Comptroller of the Currency (OCC) this month identified, isolated and resolved a security incident invo ... Read full article.