Hackers stole Pentagon personnel records of over 3 million people

The Pentagon's Defense Manpower Data Center (DMDC) suffered a significant data breach in October 2025, resulting in the theft of personnel records belonging to over 3 million military service members. The breach targeted the Pentagon's human resources management system. DMDC has begun notifying affected individuals. The scale of the breach makes it a major national security concern, as sensitive military personnel data was compromised. The incident highlights vulnerabilities in critical government HR infrastructure. The stolen data likely includes personally identifiable information (PII) of active and potentially former military personnel. This type of breach can have long-lasting counterintelligence and operational security implications for the U.S. military.