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McKesson breach, with 284 million patient records claimed
McKesson confirmed third-party app access. The record count is the attackers' unverified claim.
- Organisation
- McKesson
- Disclosed
- 28 August 2026
- Affected
- 284,000,000 (claimed by attacker, unconfirmed)
- Data
- Patient data
- Attacker
- ShinyHunters
- Severity
- critical
- Region
- Global
- Source
- CM Alliance monthly roundup ↗
Cite this
Nuffield Consulting, “McKesson breach, with 284 million patient records claimed”, The Daily Tech Wire outage & breach log, 28 Aug 2026. https://techwire.nuffieldconsulting.com/incidents/2026-08-28-mckesson-breach/ (retrieved 15 Nov 2026).
This entry summarises public reporting. Please also cite the original source: CM Alliance monthly roundup, https://www.cm-alliance.com/cybersecurity-blog/major-cyber-attacks-data-breaches-ransomware-attacks-in-august-2026.
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