Quest Diagnostics: unauthorized access to test ordering system
Hackers got into a system that some clinics and doctors use to order lab tests and look up results. Patient information in that system may have been exposed.
| Severity | UnratedData breach |
|---|---|
| Being exploited? | UnclearNo reports either way yet |
| What to do | Check exposureIf you use Quest Diagnostics services or Quanum LSM, watch for official notices from Quest and verify any follow-up contact about your lab results. |
| How sure is this? | 1 source, unconfirmedOnly one publisher so far, details may change |
What happened
Unauthorized access to Quest Diagnostics' Quanum LSM system, which clients use to place test orders and view results; the company disclosed the incident in an SEC 8-K filing dated October 21, 2026.
Are you affected?
You are affected if you are a client that uses Quest Diagnostics' Quanum LSM system to place test orders or receive and look up results.
Quest Diagnostics Quanum LSM system (client ordering and results lookup)
What to do
- Check for notices from Quest Diagnostics about whether your data was involved
- Watch for unexpected emails or calls referencing lab tests and ask for verification
- If you are a client using Quanum LSM, follow Quest's guidance and contact their support team
Timeline
- 27 Oct 2026, 18:20 UTCPublicly disclosed
- 27 Oct 2026, 18:20 UTCReported by DataBreaches.net · DataBreaches.net
- 27 Oct 2026, 18:35 UTCPicked up by Zero Radar
Sources 1 report, oldest first
Security press established security newsrooms
- Quest Diagnostics Incorporated notifies SEC of IncidentDataBreaches.net · 27 Oct 2026, 18:20 UTC
Technical details
- ID
- ZR-029d7b6a
- Disclosed
- 27 Oct 2026, 18:20 UTC
- On Zero Radar
- 27 Oct 2026, 18:35 UTC (16 min after disclosure)
- Last change
- 27 Oct 2026, 18:35 UTC
The plain-language parts and the attack diagram were written by an AI model (anthropic/claude-haiku-5.5) from the sources above. Facts like versions, exploitation and dates come from the sources themselves. How Zero Radar works