Bug 2525398 (CVE-2026-80676)

Summary: CVE-2026-80676 kernel: Drivers: hv: vmbus: use generic driver_override infrastructure
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's Hyper-V (hv) VMBus driver. When a driver is being initialized, a specific callback function attempts to access a memory region (`driver_override`) without proper synchronization. This oversight can lead to a Use-After-Free (UAF) vulnerability, where a local attacker could potentially exploit this to cause a system crash (denial of service) or execute unauthorized code.
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Description OSIDB Bzimport 2026-08-28 07:42:59 UTC 
In the Linux kernel, the following vulnerability has been resolved:

Drivers: hv: vmbus: use generic driver_override infrastructure

When a driver is probed through __driver_attach(), the bus' match()
callback is called without the device lock held, thus accessing the
driver_override field without a lock, which can cause a UAF.

Fix this by using the driver-core driver_override infrastructure taking
care of proper locking internally.

Note that calling match() from __driver_attach() without the device lock
held is intentional. [1]
Comment 1 gkamathe 2026-08-31 10:09:27 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026082849-CVE-2026-80676-5684@gregkh/T