Bug 2502409 (CVE-2026-63987)

Summary:	CVE-2026-63987 kernel: ethtool: coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES
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 ethtool subsystem. The ethnl_update_profile() function, responsible for updating profile settings, does not properly validate user-controlled input when processing Netlink nest lists. This allows a local attacker to cause an out-of-bounds write, potentially leading to a denial of service or other memory corruption issues.	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 2026-07-19 16:06:36 UTC

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

ethtool: coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES

ethnl_update_profile() walks the ETHTOOL_A_PROFILE_IRQ_MODERATION
nest list with an index 'i' and writes new_profile[i++] without
bounding i. The destination is kmemdup()'d at NET_DIM_PARAMS_NUM_PROFILES
entries (5), but the Netlink nest count is entirely user-controlled.
Netlink policies do not have support for constraining the number
of nested entries (or number of multi-attr entries).

Comment 1 Keith Grant 2026-07-21 23:40:40 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026071903-CVE-2026-63987-bda5@gregkh/T