CVE-2025-38556

In the Linux kernel, the following vulnerability has been resolved: HID: core: Harden s32ton() against conversion to 0 bits Testing by the syzbot fuzzer showed that the HID core gets a shift-out-of-bounds exception when it tries to convert a 32-bit quantity to a 0-bit quantity. Ideally this should never occur, but there are buggy devices and some might have a report field with size set to zero; we shouldn't reject the report or the device just because of that. Instead, harden the s32ton() routine so that it returns a reasonable result instead of crashing when it is called with the number of bits set to 0 -- the same as what snto32() does.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/3c86548a20d7bc2861aa4de044991a327bebad1a
https://git.kernel.org/stable/c/6cdf6c708717c5c6897d0800a1793e83757c7491
https://git.kernel.org/stable/c/810189546cb6c8f36443ed091d91f1f5d2fc2ec7
https://git.kernel.org/stable/c/865ad8469fa24de1559f247d9426ab01e5ce3a56	Patch
https://git.kernel.org/stable/c/8b4a94b1510f6a46ec48494b52ee8f67eb4fc836	Patch
https://git.kernel.org/stable/c/a6b87bfc2ab5bccb7ad953693c85d9062aef3fdd	Patch
https://git.kernel.org/stable/c/d3b504146c111548ab60b6ef7aad00bfb1db05a2	Patch
https://git.kernel.org/stable/c/eeeaba737919bdce9885e2a00ac2912f61a3684d

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2025-08-19 17:15

Updated : 2026-01-19 13:16

NVD link : CVE-2025-38556

Mitre link : CVE-2025-38556

CVE.ORG link : CVE-2025-38556

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-125

Out-of-bounds Read

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