CVE-2026-74552 json
hwmon: (lm90) Only report alarms if driver is ready
published 2026-08-15 2 mo ago modified 2026-08-19 2 mo ago also EUVD-2026-59617
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 6%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
hwmon: (lm90) Only report alarms if driver is ready
Userspace can read sysfs attributes before driver registration is complete, immediately after devm_hwmon_device_register_with_info() has been called. At that time, data->hwmon_dev is not yet initialized. This can trigger a NULL pointer access since lm90_update_device() and with it lm90_update_alarms_locked() will be called. This call schedules report_work and lm90_report_alarms(), which passes the still-NULL data->hwmon_dev to hwmon_notify_event() and triggers a NULL pointer dereference.
Fix the problem by only scheduling the report and alert workers data->hwmon_dev is set.
Patch / fix
- Linux Linux 6.1.183, 6.6.151, 6.12.103, 6.18.44, 7.1.8, 7.2
- linux Debian 12 6.1.187-1
- linux Debian 13 6.12.105-1
- linux Debian 14 7.1.8-1
- linux-6.12 Debian 12 6.12.107-1~deb12u1
debian advisories DEBIAN-CVE-2026-74552
- linux Ubuntu 26.04 LTS 7.0.0-42.42
- linux-aws Ubuntu 26.04 LTS 7.0.0-1016.17
- linux-gcp Ubuntu 26.04 LTS 7.0.0-1016.18
- linux-ibm Ubuntu 26.04 LTS 7.0.0-1017.17
- linux-riscv Ubuntu 26.04 LTS 7.0.0-42.42.1
- linux-oracle Ubuntu 26.04 LTS 7.0.0-1015.16
- linux-hwe-7.0 Ubuntu 24.04 LTS 7.0.0-42.42~24.04.1
- linux-oem-7.0 Ubuntu 26.04 LTS 7.0.0-1017.17
ubuntu advisories UBUNTU-CVE-2026-74552
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel-source Linux Micro 6.0 6.4.0-159998.55.1
- kernel-default Linux Micro 6.0 6.4.0-159998.55.1
- kernel-kvmsmall Linux Micro 6.0 6.4.0-159998.55.1
- kernel-default-base Linux Micro 6.0 6.4.0-159998.55.1.159998.21.42
- kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.90.1
- kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.90.1
- kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.90.1
- kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.90.1
suse advisories SUSE-SU-2026:24550-1SUSE-SU-2026:5091-1
- git.kernel.org/stable/c/31ce62d36d859423dc39f9902f7c4c307b2e00e3 commit
- git.kernel.org/stable/c/4eed33c7db5c0c573928d28d8a2c003642c679b8 commit
- git.kernel.org/stable/c/70d9a71aa407044d70b50d356b6decf6659c4d56 commit
- git.kernel.org/stable/c/075fce376cf852db9293481edce07c181a9b1f46 commit
- git.kernel.org/stable/c/f0b791a006512a48b6348494cb6960598fa99a58 commit
- git.kernel.org/stable/c/aa9429edf9fc0e90d6f4da19ea4b5495a54ab117 commit
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-74552 updated cvss 5.5
kernel: hwmon: (lm90) Only report alarms if driver is ready
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 moreaffected: workaround, no fix planned “Out of support scope”
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Red Hat Enterprise Linux 10 kernelaffected: workaround, no fix available “Fix deferred”
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Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 morenot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-08).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/31ce62d36d859423dc39f9902f7c4c307b2e00e3
- git.kernel.org /stable/c/4eed33c7db5c0c573928d28d8a2c003642c679b8
- git.kernel.org /stable/c/70d9a71aa407044d70b50d356b6decf6659c4d56
- git.kernel.org /stable/c/075fce376cf852db9293481edce07c181a9b1f46
- git.kernel.org /stable/c/f0b791a006512a48b6348494cb6960598fa99a58
- git.kernel.org /stable/c/aa9429edf9fc0e90d6f4da19ea4b5495a54ab117
Sources
- CVE List CVE-2026-74552
- NVD CVE-2026-74552
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