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Fencer Vulns
high 7.8

CVE-2026-23323 json

hwmon: (macsmc) Fix regressions in Apple Silicon SMC hwmon driver

published 2026-03-25 7 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-15276

cvss
7.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 3%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

hwmon: (macsmc) Fix regressions in Apple Silicon SMC hwmon driver

The recently added macsmc-hwmon driver contained several critical bugs in its sensor population logic and float conversion routines.

Specifically: - The voltage sensor population loop used the wrong prefix ("volt-" instead of "voltage-") and incorrectly assigned sensors to the temperature sensor array (hwmon->temp.sensors) instead of the voltage sensor array (hwmon->volt.sensors). This would lead to out-of-bounds memory access or data corruption when both temperature and voltage sensors were present. - The float conversion in macsmc_hwmon_write_f32() had flawed exponent logic for values >= 2^24 and lacked masking for the mantissa, which could lead to incorrect values being written to the SMC.

Fix these issues to ensure correct sensor registration and reliable manual fan control.

Confirm that the reported overflow in FIELD_PREP is fixed by declaring macsmc_hwmon_write_f32() as __always_inline for a compile test.

Patch / fix

  • Linux Linux 6.19.7, 7.0
  • linux Debian 14 6.19.8-1

debian advisories DEBIAN-CVE-2026-23323

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-2026-23323 updated

kernel: hwmon: (macsmc) Fix regressions in Apple Silicon SMC hwmon driver

  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more 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 more Red Hat Enterprise Linux 10 kernel
    not 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

0.14% chance of exploitation in the next 30 days, higher than 3% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Linux Linux

Classification

Weakness
Technology feeds

References

Sources

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