CVE-2026-46142: net: libwx: fix VF illegal register access
In the Linux kernel, the following vulnerability has been resolved:
net: libwx: fix VF illegal register access
Register WXCFGPORTST is a PF restricted register. When a VF is initialized, attempting to read this register triggers an illegal register access, which lead to a system hang.
When the device is VF, the bus function ID can be obtained directly from the PCIFUNC(pdev->devfn).
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.141.1-1
Event History
Frequently Asked Questions
Which systems are exposed to this issue?
Systems using the Linux kernel net/libwx component with a virtual function (VF) of the affected device are exposed. The listed affected software includes the Linux kernel and Microsoft azl3 kernel 6.6.139.1-1.
What access does an attacker need to trigger the impact?
The supplied CVSS vector indicates local access and low privileges are required, with no user interaction. The failure occurs when VF initialization attempts to read the PF-restricted WX_CFG_PORT_ST register.
What is the impact if the vulnerable register access occurs?
Reading WX_CFG_PORT_ST from a VF triggers an illegal register access that can cause a system hang. The CVSS vector indicates availability impact only, with no stated confidentiality or integrity impact.
What is the available remediation?
Apply a kernel update containing the resolved net/libwx change. The fix obtains the VF bus function ID directly through PCI_FUNC(pdev->devfn), avoiding the PF-restricted register access.