Bug 2555094 (CVE-2026-98702)

Summary:	CVE-2026-98702 kernel: kernel: Denial of Service via invalid channel switch frame in mac80211
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
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 mac80211 wireless subsystem. A nearby wireless attacker can cause a Denial of Service (DoS) by sending a crafted Channel Switch Announcement (CSA) frame with an unsupported bandwidth configuration. Because the kernel fails to reject this channel definition, it reads uninitialized memory and can trigger a system crash.	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 2026-10-18 15:54:04 UTC

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

wifi: mac80211: reject invalid 320 MHz CSA bandwidth

The HT/VHT channel definition validator can receive a 320 MHz
bandwidth indication from a received CSA frame on a non-6 GHz link.
It warns for this unsupported width but continues with an uninitialized
vht_operation.chan_width, which is then read by
ieee80211_chandef_vht_oper(). With panic_on_warn enabled, this lets a
received frame panic the kernel.

Reject the channel definition before entering the VHT operation
conversion. This preserves the existing CSA fallback while avoiding
both the warning and the uninitialized read.