Monthly roundup

Data breaches in August 2026

3 incidents across 2 countries. 3 confirmed by the organization or authorities; the rest are under investigation or claimed by attackers.

Short answer

August 2026 brought 3 breaches and cyber attacks that we could verify, in United States, Germany. If you use any of these services, expect phishing that mentions the incident, and follow our data breach checklist.

United States

  • Apollo Management Holdings, L.P.: data breach

    Apollo, the private equity and credit firm, told people in letters dated 21 August 2026 that it suffered a social engineering incident. Unauthorized parties accessed certain cloud platforms between 6 and 10 July 2026, and on 12 August Apollo learned personal information was potentially affected. It has not said how many people are involved.

    Confirmed by the organization United States · Financial services (alternative asset management)
  • Quantum Health, Inc.: data breach

    Quantum Health, a Dublin, Ohio company that coordinates care for members of employer health plans, says a user answered a vishing call on 29 May 2026 and an unauthorized party then accessed and took files until 1 June. The company confirmed on 8 July that some files held member information and began notifying plans on 27 July.

    Confirmed by the organization United States · Healthcare navigation (self-insured employer health plans)

Germany

  • State of Berlin (Berlin Senate administration): ransomware

    Berlin's government confirmed in late August 2026 that criminals had stolen data from its administrative network and were trying to extort the state. The group Rhysida claims 5.79 TB. Governing Mayor Kai Wegner said Berlin will not pay, and the state says election systems were not affected.

    Confirmed by the organization Germany · State and city government

All breaches