Breaches and incidentsBriefChecked against a primary source
Quest Diagnostics: unauthorized access to Quanum LSM lab ordering and results system
Quest’s Form 8-K says it learned on 21 Oct 2026 of “unauthorized access to its Quanum LSM system”, which certain clients use to place test orders and...
- Disclosed
What happened
- Quest’s Form 8-K says it learned on 21 Oct 2026 of “unauthorized access to its Quanum LSM system”, which certain clients use to place test orders and receive and look up results, and believes an unauthorized party accessed certain patient records. The number of patients and record types were not disclosed; Quest said business operations and service to patients were not materially disrupted.
- Root cause / initial access: not disclosed.
- Attacker: not identified.
- Response: incident response activated, federal law enforcement notified, external experts engaged; scope under investigation.
Sources
- https://www.sec.gov/Archives/edgar/data/1022079/000094787126000941/ss6979200_8k.htm
- https://www.reuters.com/legal/litigation/laboratory-operator-quest-reports-cyber-breach-affecting-patient-records-2026-10-22/
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