CVE-2021-47386

hwmon: (w83791d) Fix NULL pointer dereference by removing unnecessary structure field

HIGH
7.8
CVSS Score
Published: May 21, 2024 at 03:03 PM UTC
Updated: June 17, 2026 at 04:17 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH7.8
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: hwmon: (w83791d) Fix NULL pointer dereference by removing unnecessary structure field If driver read val value sufficient for (val & 0x08) && (!(val & 0x80)) && ((val & 0x7) == ((val >> 4) & 0x7)) from device then Null pointer dereference occurs. (It is possible if tmp = 0b0xyz1xyz, where same literals mean same numbers) Also lm75[] does not serve a purpose anymore after switching to devm_i2c_new_dummy_device() in w83791d_detect_subclients(). The patch fixes possible NULL pointer dereference by removing lm75[]. Found by Linux Driver Verification project (linuxtesting.org). [groeck: Dropped unnecessary continuation lines, fixed multi-line alignment]

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 5.4.1515.11 ≤ v < 5.14.105.4 ≤ v < 5.10.715.4 ≤ v < 5.14.105.4 ≤ v < 5.155.4 ≤ v < 5.4.1515.5 ≤ v < 5.10.71358d2071100d84cfe6ef4a9d70ac0d998a1d501e5.15 rc15.15 rc25.15 rc3
Vendor states this is fixed in 16887ae4e3defd2c4e7913b6c539f33eaf4eac5c (fixed)
Vendor states this is fixed in 44d3c480e4e2a75bf6296a18b4356157991ccd80 (fixed)
Vendor states this is fixed in 516d9055039017a20a698103be2b556b4c976bb8 (fixed)
Vendor states this is fixed in 943c15ac1b84d378da26bba41c83c67e16499ac4 (fixed)
Vendor states this is fixed in 5.10.71 (unaffected)
Vendor states this is fixed in 5.14.10 (unaffected)
Vendor states this is fixed in 5.15 (unaffected)
Vendor states this is fixed in 5.4 (unaffected)
Vendor states this is fixed in 5.4.151 (unaffected)

References (4)

Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/16887ae4e3defd2c4e7913b6c539f33eaf4eac5c
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/44d3c480e4e2a75bf6296a18b4356157991ccd80
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/516d9055039017a20a698103be2b556b4c976bb8
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/943c15ac1b84d378da26bba41c83c67e16499ac4

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.8HIGHCISA-ADP
Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-476

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