Bug 2536403 (CVE-2026-90419)

Summary:	CVE-2026-90419 kernel: nilfs2: prevent out-of-bounds read in super root block parsing
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:	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 nilfs2 filesystem implementation within the Linux kernel. This vulnerability occurs due to insufficient validation of super-root inode metadata size before parsing. A local attacker could craft a malicious filesystem image that, when processed, causes an out-of-bounds read past the end of the super-root block. This could lead to information disclosure or a denial of service.	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 2026-09-17 17:44:31 UTC

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

nilfs2: prevent out-of-bounds read in super root block parsing

super-root inode metadata size is trusted before nilfs_read_inode_common().

Reject super-root inode sizes whose computed on-disk footprint exceeds the
filesystem block size. This prevents malformed filesystem images from
making nilfs_read_inode_common() read past the end of the super-root block.

[ryusuke: clarify the commit title]

Comment 1 gkamathe 2026-09-21 12:45:14 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90419.mbox