CVE-2026-43431: xhci: Fix NULL pointer dereference when reading portli debugfs files

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-08 · updated 2026-06-17
Weakness: CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: xhci: Fix NULL pointer dereference when reading portli debugfs files Michal reported and debgged a NULL pointer dereference bug in the recently added portli debugfs files Oops is caused when there are more port registers counted in xhci->max_ports than ports reported by Supported Protocol capabilities. This is possible if max_ports is more than maximum port number, or if there are gaps between ports of different speeds the 'Supported Protocol' capabilities. In such cases port->rhub will be NULL so we can't reach xhci behind it. Add an explicit NULL check for this case, and print portli in hex without dereferencing port->rhub.

Affected products

Linux kernel: from 6.19 before 6.19.9; 7.0-rc1, 7.0-rc2, 7.0-rc3, 7.0-rc4 — fixed in 6.19.9

How to fix

Upgrade to a fixed version: Linux kernel 6.19.9. Check the vendor advisory for mitigations.

References

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