Bug 2541363 (CVE-2026-98113)

Summary:	CVE-2026-98113 kernel: ksmbd: rate limit unmapped SID errors
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 ksmbd server. An authenticated remote client can cause a Denial of Service (DoS) by sending requests containing multiple unmapped Security Identifiers (SIDs) within a Discretionary Access Control List (DACL). Because the server logs each mapping failure without rate limiting, a single request can generate hundreds of error messages. This allows an attacker to flood the kernel log, potentially exhausting storage or degrading system performance.	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 2026-09-25 11:34:18 UTC

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

ksmbd: rate limit unmapped SID errors

A client can include many structurally valid but unmapped SIDs in a DACL.
Logging every mapping failure lets one request generate hundreds of kernel
error messages.

Rate limit the message to prevent an authenticated client from flooding
the kernel log.

Comment 1 Keith Grant 2026-09-28 12:34:05 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98113.mbox