# CVE-2026-31582: hwmon: (powerz) Fix use-after-free on USB disconnect

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-04-24 · Updated: 2026-06-14

## Affected

- Linux: version range not reported
- Linux: 6.7

## Description

In the Linux kernel, the following vulnerability has been resolved: hwmon: (powerz) Fix use-after-free on USB disconnect After powerz_disconnect() frees the URB and releases the mutex, a subsequent powerz_read() call can acquire the mutex and call powerz_read_data(), which dereferences the freed URB pointer. Fix by: - Setting priv->urb to NULL in powerz_disconnect() so that powerz_read_data() can detect the disconnected state. - Adding a !priv->urb check at the start of powerz_read_data() to return -ENODEV on a disconnected device. - Moving usb_set_intfdata() before hwmon registration so the disconnect handler can always find the priv pointer.

## 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.
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## 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/c78e1d4e48f23792adaa7c94251e22b0d9700a39
- https://git.kernel.org/stable/c/9e1b798257f96d2e2a2639830eb71add545ce749
- https://git.kernel.org/stable/c/7003ae4810ca83f0ddca85b768500e313c4b998c
- https://git.kernel.org/stable/c/61f2aa23b0ce8d7aa5071ed25a7471e246a4fdd4
- https://git.kernel.org/stable/c/08e57f5e1a9067d5fbf33993aa7f51d60b3d13a4

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Page: https://cve.now/CVE-2026-31582
JSON: https://cve.now/api/v1/entries/CVE-2026-31582
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