Bug 2482004 (CVE-2026-46018)

Summary:	CVE-2026-46018 kernel: ALSA: usb-audio: stop parsing UAC2 rates at MAX_NR_RATES
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
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 Advanced Linux Sound Architecture (ALSA) USB audio driver. A malicious Universal Serial Bus (USB) audio device could send a malformed Universal Audio Class 2 (UAC2) RANGE response. This could cause the system to repeatedly print error messages and potentially lead to a denial of service (DoS) by holding a mutex during the device probing process.	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 2026-05-27 15:06:36 UTC

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

ALSA: usb-audio: stop parsing UAC2 rates at MAX_NR_RATES

parse_uac2_sample_rate_range() caps the number of enumerated
rates at MAX_NR_RATES, but it only breaks out of the current
rate loop. A malformed UAC2 RANGE response with additional
triplets continues parsing the remaining triplets and repeatedly
prints "invalid uac2 rates" while probe still holds
register_mutex.

Stop the whole parse once the cap is reached and return the
number of rates collected so far.

Comment 1 Keith Grant 2026-05-27 20:34:04 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026052746-CVE-2026-46018-ac95@gregkh/T