Description
In the Linux kernel, the following vulnerability has been resolved:

hwmon: Fix potential UAF in pec_store

Sashiko reports:

In pec_store(), a guard(mutex)(&hwdev->lock) is taken. If the chip write
operation returns an error other than -EOPNOTSUPP, the code jumps to the
put label, which calls put_device(hdev). If this drops the final reference,
the device is freed. When the function then returns, the guard cleanup
function runs and attempts to unlock the freed mutex.

Use scoped_guard() instead of guard() to avoid the problem.
Published: 2026-09-25
Score: n/a
EPSS: n/a
KEV: No
Impact: Use-After-Free in the Linux kernel hardware monitoring subsystem could lead to a kernel crash or potential code execution
Action: Apply Patch
AI Analysis

Impact

In the hwmon subsystem of the Linux kernel, a guard around the device mutex is released after freeing the device if a write operation fails with an error other than -EOPNOTSUPP. This sequence causes a use‑after‑free of the mutex, which can trigger a kernel panic or, in certain contexts, arbitrary code execution. The weakness is a classic Use‑After‑Free flaw (CWE‑416).

Affected Systems

All Linux kernel versions that contain the buggy pec_store implementation are affected. The fix is included in the kernel series following the patch commit referenced in the advisory; upgrading to any kernel that incorporates that commit mitigates the issue.

Risk and Exploitability

The CVSS score is not listed, and the EPSS score is not available, indicating that the exploit probability is not publicly quantified. The vulnerability is not listed in the CISA KEV catalog. Based on the description, the likely attack vector is a local privileged user who can trigger a failing hwmon write and exploit the use‑after‑free to crash the system or gain code execution at kernel level.

Generated by OpenCVE AI on September 25, 2026 at 15:26 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Upgrade the Linux kernel to a release that includes the pec_store patch commit; the update replaces the guard with a scoped_guard to eliminate the use‑after‑free.
  • Reboot the system after upgrading to ensure the patched kernel is in use and the offending mutex logic is removed.
  • If an urgent upgrade is not possible, disable the hwmon subsystem or the specific device driver that uses pec_store to prevent the vulnerable code from running until a fix is applied.

Generated by OpenCVE AI on September 25, 2026 at 15:26 UTC.

Tracking

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Advisories

No advisories yet.

History

Fri, 25 Sep 2026 15:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416

Fri, 25 Sep 2026 10:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: hwmon: Fix potential UAF in pec_store Sashiko reports: In pec_store(), a guard(mutex)(&hwdev->lock) is taken. If the chip write operation returns an error other than -EOPNOTSUPP, the code jumps to the put label, which calls put_device(hdev). If this drops the final reference, the device is freed. When the function then returns, the guard cleanup function runs and attempts to unlock the freed mutex. Use scoped_guard() instead of guard() to avoid the problem.
Title hwmon: Fix potential UAF in pec_store
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-09-25T10:23:28.703Z

Reserved: 2026-09-25T10:19:56.068Z

Link: CVE-2026-98000

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-25T11:17:28.213

Modified: 2026-09-25T11:17:28.213

Link: CVE-2026-98000

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-25T15:30:06Z

Weaknesses