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CVE-2026-31486

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus/core) Protect regulator operations with mutex The regulator operations pmbus_regulator_get_voltage(), pmbus_regulator_set_voltage(), and pmbus_regulator_list_voltage() access PMBus registers and shared data but were not protected by the update_lock mutex. This could lead to race conditions. However, adding mutex protection directly to these functions causes a deadlock because pmbus_regulator_notify() (which calls regulator_notifier_call_chain()) is often called with the mutex already held (e.g., from pmbus_fault_handler()). If a regulator callback then calls one of the now-protected voltage functions, it will attempt to acquire the same mutex. Rework pmbus_regulator_notify() to utilize a worker function to send notifications outside of the mutex protection. Events are stored as atomics in a per-page bitmask and processed by the worker. Initialize the worker and its associated data during regulator registration, and ensure it is cancelled on device removal using devm_add_action_or_reset(). While at it, remove the unnecessary include of linux/of.h.

Severity
HIGH
CVSS score
7.1 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-04-22 14:16:46.160000
Last modified
2026-10-30 13:18:40.083000
View original CVE JSON 
{
  "id": "CVE-2026-31486",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-04-22T14:16:46.160",
  "lastModified": "2026-10-30T13:18:40.083",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pmbus/core) Protect regulator operations with mutex\n\nThe regulator operations pmbus_regulator_get_voltage(),\npmbus_regulator_set_voltage(), and pmbus_regulator_list_voltage()\naccess PMBus registers and shared data but were not protected by\nthe update_lock mutex. This could lead to race conditions.\n\nHowever, adding mutex protection directly to these functions causes\na deadlock because pmbus_regulator_notify() (which calls\nregulator_notifier_call_chain()) is often called with the mutex\nalready held (e.g., from pmbus_fault_handler()). If a regulator\ncallback then calls one of the now-protected voltage functions,\nit will attempt to acquire the same mutex.\n\nRework pmbus_regulator_notify() to utilize a worker function to\nsend notifications outside of the mutex protection. Events are\nstored as atomics in a per-page bitmask and processed by the worker.\n\nInitialize the worker and its associated data during regulator\nregistration, and ensure it is cancelled on device removal using\ndevm_add_action_or_reset().\n\nWhile at it, remove the unnecessary include of linux/of.h."
    }
  ],
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          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
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      "source": "[email protected]",
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