Microsoft Security Response Center guidance
Vendor revision: Sep 24, 2026Release Notes
Vulnerability intelligence
CVE-2026-64213 and is rated Medium severity with a CVSS score of 5.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
Release Notes
In the Linux kernel, the following vulnerability has been resolved:
hwmon: (lm90) Add lock protection to lm90_alert
Sashiko reports:
lm90_alert() executes in the smbus alert context and calls lm90_update_confreg() to disable the hardware alert line, without acquiring hwmon_lock.
Concurrently, sysfs write operations (such as lm90_write_convrate) hold the hwmon_lock, temporarily modify data->config, and then restore it.
If an alert interrupt occurs concurrently with a sysfs write, the sysfs path will overwrite the alert handler's modifications to data->config and the hardware register.
This unintentionally re-enables the hardware alert line while the alarm is still active, causing an interrupt storm.
Add the missing lock to lm90_alert() to solve the problem.
Source: NVD