Bug 2541060 (CVE-2026-97929)

Summary:	CVE-2026-97929 kernel: ALSA: usbusx2y: validate URB actual_length in interrupt callback
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:	akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, 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 ALSA (Advanced Linux Sound Architecture) USB audio driver. This vulnerability can lead to information disclosure when communicating with an attached USB device. The driver fails to verify the length of incoming data transfers during interrupt handling, allowing uninitialized kernel memory to be copied into memory buffers accessible by user applications. An attacker who connects a crafted or malfunctioning USB device can exploit this issue to expose sensitive kernel information to local users.	Story Points:	---
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Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-09-25 10:45:04 UTC

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

ALSA: usbusx2y: validate URB actual_length in interrupt callback

i_usx2y_in04_int() processes the interrupt URB data without checking
urb->actual_length.  A short transfer from a malfunctioning device
would cause the handler to process uninitialized heap data from the
kmalloc-allocated in04_buf, which is then copied to the mmap-accessible
ctl_snapshot[] array.

Fix by using kzalloc() for in04_buf to zero-initialize the buffer,
and adding an actual_length check to skip processing on short
transfers while still resubmitting the URB.

Comment 1 Keith Grant 2026-09-29 19:56:44 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97929.mbox