Bug 2540405 (CVE-2026-93789)

Summary:	CVE-2026-93789 kernel: wifi: iwlwifi: bound aligned TLV advance in FW parser
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 iwlwifi driver. This vulnerability allows a local user capable of loading custom firmware to cause a Denial of Service (DoS) through a system crash. The issue stems from insufficient bounds checking when parsing aligned Type-Length-Value (TLV) data blocks within firmware images. By supplying a crafted firmware file, an attacker can trigger an integer underflow, leading to out-of-bounds memory reads.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
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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 2026-09-24 16:42:41 UTC

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

wifi: iwlwifi: bound aligned TLV advance in FW parser

Validate ALIGN(tlv_len, 4) against remaining parser length before
consuming bytes from the firmware image.

This avoids length underflow on malformed TLVs.

Comment 1 Mauro Matteo Cascella 2026-09-28 10:53:56 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-93789.mbox