Network disruption via missed virtual-function registration
Published Apr 17, 2024 · Updated May 23, 2026
Race condition in the Linux kernel hv_netvsc driver allows local users to disrupt Hyper-V virtual-function registration by reloading the driver. The driver registers its netdevice notifier before vmbus_driver_register, so NET_DEVICE_REGISTER can arrive before netvsc_probe finishes and the handler misses the virtual function. Triggering the condition requires privileges to unload and reload the driver; the resulting unregistered virtual function can interrupt accelerated network connectivity.
Summary
What happened
Race condition in the Linux kernel hv_netvsc driver allows local users to disrupt Hyper-V virtual-function registration by reloading the driver. The driver registers its netdevice notifier before vmbus_driver_register, so NET_DEVICE_REGISTER can arrive before netvsc_probe finishes and the handler misses the virtual function. Triggering the condition requires privileges to unload and reload the driver; the resulting unregistered virtual function can interrupt accelerated network connectivity.
The record
- CVE
- CVE-2024-26820
- Published
- Apr 17, 2024
- Updated
- May 23, 2026
- Vendor
- Siemens
- Product
- SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
- Classifications
- T1499
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Apr 17, 2024CVE publishedPublication date reported by the CVE source.
- May 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
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- Affected versionversion=0 <*
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Published CVSS scores
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Attacks
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Technologies
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