Bug 2467235 (CVE-2026-43140)

Summary:	CVE-2026-43140 kernel: HID: magicmouse: Do not crash on missing msc->input
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the Linux kernel's HID (Human Interface Device) magicmouse driver. A local attacker with physical access could exploit this vulnerability by connecting a specially crafted USB device. This device could send a malformed report descriptor, causing the `msc->input` to remain uninitialized, which leads to a system crash. This issue results in a Denial of Service (DoS) for the affected system.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-05-06 13:12:19 UTC

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

HID: magicmouse: Do not crash on missing msc->input

Fake USB devices can send their own report descriptors for which the
input_mapping() hook does not get called.  In this case, msc->input stays NULL,
leading to a crash at a later time.

Detect this condition in the input_configured() hook and reject the device.

This is not supposed to happen with actual magic mouse devices, but can be
provoked by imposing as a magic mouse USB device.

Comment 1 Keith Grant 2026-05-06 18:23:56 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026050624-CVE-2026-43140-1367@gregkh/T