Zero Radar
← feed
LeakData breachupdated 27 Oct 2026, 18:35 UTC

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.

1 source, unconfirmed
SeverityUnratedData breach
Being exploited?UnclearNo reports either way yet
What to doCheck 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.

Why it is dangerous: Test orders and lab results can contain sensitive health information, so patients and the clients who use the system may be at risk of privacy harm. The full scope of data involved is not stated in the material.

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

  1. Check for notices from Quest Diagnostics about whether your data was involved
  2. Watch for unexpected emails or calls referencing lab tests and ask for verification
  3. If you are a client using Quanum LSM, follow Quest's guidance and contact their support team

Timeline

  1. 27 Oct 2026, 18:20 UTC
    Publicly disclosed
  2. 27 Oct 2026, 18:20 UTC
    Reported by DataBreaches.net · DataBreaches.net
  3. 27 Oct 2026, 18:35 UTC
    Picked up by Zero Radar

Sources 1 report, oldest first

Security press established security newsrooms

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

Quest Diagnostics: unauthorized access to test ordering system · Zero Radar