Bug 2464444 (CVE-2026-31752)

Summary:	CVE-2026-31752 kernel: bridge: br_nd_send: validate ND option lengths
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 bridge module. A remote attacker could exploit this by sending a malformed Neighbor Discovery (ND) option. This could cause the `br_nd_send()` function to improperly process option lengths, potentially leading to information disclosure or a denial of service (DoS).	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 2026-05-01 15:07:09 UTC

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

bridge: br_nd_send: validate ND option lengths

br_nd_send() walks ND options according to option-provided lengths.
A malformed option can make the parser advance beyond the computed
option span or use a too-short source LLADDR option payload.

Validate option lengths against the remaining NS option area before
advancing, and only read source LLADDR when the option is large enough
for an Ethernet address.

Comment 1 Keith Grant 2026-05-01 22:08:38 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026050143-CVE-2026-31752-5596@gregkh/T