CVE-2026-31486: Linux kernel · hwmon: (pmbus/core) Protect regulator operations with mutex
Source GCVE Database
Not known to be exploited · CVSS 7.1 High · fixed in f0c9ea9c3a208e79c812e10e2bcef87b46564f01 : patch Linux kernel soon.
Data as of 30 Oct 2026, 16:33 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 7.1 |
|---|
- Patch
- Available – fixed in f0c9ea9c3a208e79c812e10e2bcef87b46564f01, b26849cffaa7c43355b82e9bef3725e786973a1a, acf04e2863132f6d9222f71f3a76fb9782cbe061 +3
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 22 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
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.
References
- nvd.nist.gov/vuln/detail/CVE-2026-31486 (opens in a new tab)
- git.kernel.org/stable/c/2c77ae315f3ce9d2c8e1609be74c9358c1fe4e07 (opens in a new tab)
- git.kernel.org/stable/c/4e9d723d9f198b86f6882a84c501ba1f39e8d055 (opens in a new tab)
- git.kernel.org/stable/c/754bd2b4a084b90b5e7b630e1f423061a9b9b761 (opens in a new tab)
- git.kernel.org/stable/c/acf04e2863132f6d9222f71f3a76fb9782cbe061 (opens in a new tab)
- git.kernel.org/stable/c/b26849cffaa7c43355b82e9bef3725e786973a1a (opens in a new tab)
- git.kernel.org/stable/c/f0c9ea9c3a208e79c812e10e2bcef87b46564f01 (opens in a new tab)