Duplicate hosts by serial number

[mason-buettner]

Fleet version: 4.70 and 4.71.0

Web browser and operating system: Chrome 138 on macOS 15.6

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💥  Actual behavior

Customers are experiencing issues related to duplicate host entries for the same serial number.

customer-redwine reports that they have 91 serial numbers with 2 device records. DB output with the relevant information here.

customer-mozartia has reported one so far. Slack thread here.

🛠️ To fix

TBD

Product designer: _________________________

🧑‍💻  Steps to reproduce

1. TODO
2. TODO

🕯️ More info (optional)

N/A

[mason-buettner]

customer-ampella has also reported the same behavior on Fleet 4.71.0.

https://fleetdm.slack.com/archives/C07UDLTSS5Q/p1754691239237509

[sharon-fdm]

@georgekarrv, this seems to be MDM related and we do not know how to reproduce.
Want to have a look?