# CVE-2026-64213: hwmon: (lm90) Add lock protection to lm90_alert

CVE-2026-64213 is fixed in 12 products on 1 platform, first by DEBIAN-CVE-2026-64213, released July 25, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-64213
- Priority: High
- CVSS: 7.1 (Important)
- EPSS: 0.0012
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 24, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64213

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | kernel-64kb sles 15.7 | 6.4.0-150700.53.84.1 | [SUSE-SU-2026:4706-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4706-1.md) | Nov 7, 2026 |
| Linux | kernel-azure sles 15.7 | 6.4.0-150700.53.84.1 | [SUSE-SU-2026:4706-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4706-1.md) | Nov 7, 2026 |
| Linux | kernel-default sles 15.7 | 6.4.0-150700.53.84.1 | [SUSE-SU-2026:4706-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4706-1.md) | Nov 7, 2026 |
| Linux | kernel-default-base sles 15.7 | 6.4.0-150700.53.84.1.150700.17.47.1 | [SUSE-SU-2026:4706-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4706-1.md) | Nov 7, 2026 |
| Linux | kernel-docs sles 15.7 | 6.4.0-150700.53.84.1 | [SUSE-SU-2026:4706-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4706-1.md) | Nov 7, 2026 |
| Linux | kernel-livepatch-SLE15-SP7-RT_Update_21 sles 15.7 | 1-150700.1.3.1 | [SUSE-SU-2026:4640-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4640-1.md) | Nov 7, 2026 |
| Linux | kernel-livepatch-SLE15-SP7_Update_22 sles 15.7 | 1-150700.15.3.1 | [SUSE-SU-2026:4706-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4706-1.md) | Nov 7, 2026 |
| Linux | kernel-obs-build sles 15.7 | 6.4.0-150700.53.84.1 | [SUSE-SU-2026:4706-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4706-1.md) | Nov 7, 2026 |
| Linux | kernel-source sles 15.7 | 6.4.0-150700.53.84.1 | [SUSE-SU-2026:4706-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4706-1.md) | Nov 7, 2026 |
| Linux | kernel-syms sles 15.7 | 6.4.0-150700.53.84.1 | [SUSE-SU-2026:4706-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4706-1.md) | Nov 7, 2026 |
| Linux | kernel-zfcpdump sles 15.7 | 6.4.0-150700.53.84.1 | [SUSE-SU-2026:4706-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4706-1.md) | Nov 7, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.115-2 | [DEBIAN-CVE-2026-64213](https://patchblox.com/security/data/fix/linux/debian-cve-2026-64213.md) | Jul 25, 2026 |
| Linux | linux Debian 14 | 7.0.12-1 | [DEBIAN-CVE-2026-64213](https://patchblox.com/security/data/fix/linux/debian-cve-2026-64213.md) | Jul 25, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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