Skip to main content

Linux Kernel XFS CVE-2026-64356

| EUVDEUVD-2026-48900 MEDIUM
Memory Leak (CWE-401)
2026-07-25 Linux GHSA-p28w-6j9h-mmp2
5.5
CVSS 3.1 · NVD
Share

Severity by source

NVD PRIMARY
5.5 MEDIUM
AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
vuln.today AI
5.5 MEDIUM

Local-only vector requiring a low-privilege mount operation; no confidentiality or integrity impact, only availability loss via memory exhaustion.

3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
4.0 AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SUSE
5.3 MEDIUM
AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:H
Red Hat
5.5 LOW
qualitative

Primary rating from NVD.

CVSS VectorNVD

Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Lifecycle Timeline

6
Metadata Corrected
Sep 04, 2026 - 16:40 vuln.today
tag: Information Disclosure removed
Analysis Generated
Sep 04, 2026 - 16:14 vuln.today
CVSS changed
Sep 04, 2026 - 16:07 NVD
5.5 (MEDIUM)
Patch available
Jul 25, 2026 - 11:18 EUVD
CVE Published
Jul 25, 2026 - 08:50 cve.org
UNKNOWN (no severity yet)
CVE Published
Jul 25, 2026 - 08:50 nvd
MEDIUM 5.5

DescriptionNVD

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

xfs: fix memory leak in xfs_dqinode_metadir_create()

If xfs_metadir_create() fails in xfs_dqinode_metadir_create(), the current code returns directly, leaking the allocated update and transaction state. If the subsequent commit fails, the caller-owned inode reference is left behind.

Fix this memory leak by routing the create failure path through xfs_metadir_cancel(). For both create and commit failures, finish and release any inode returned to the caller, mirroring the unwind pattern in xfs_metadir_mkdir().

The bug was first flagged by an experimental analysis tool we are developing for kernel memory-management bugs while analyzing v6.13-rc1. The tool is still under development and is not yet publicly available. Manual inspection confirms that the bug is still present in v7.1.1.

An x86_64 allyesconfig build showed no new warnings. Runtime validation used kprobe fault injection during mount -o uquota on a metadir XFS image. Injecting xfs_metadir_create() reproduced the old active-update path that left mount stuck later in mount setup; after this change, the same injection reported cancel_hits=1 and irele_hits=1. Injecting xfs_metadir_commit() exercised the old inode-reference leak path; after this change, it reported irele_hits=1.

AnalysisAI

Memory exhaustion in the Linux kernel XFS quota subsystem can be triggered by a local low-privilege user on systems mounting metadir XFS images with user quota enabled. The vulnerability exists in xfs_dqinode_metadir_create(), where failure of xfs_metadir_create() returns without releasing the allocated update and transaction state, and commit failures leave behind caller-owned inode references. Confirmed present from Linux 6.13-rc1 through v7.1.1; patched in stable releases 6.18.39 and 7.1.4.

Technical ContextAI

The vulnerability resides in the XFS quota subsystem of the Linux kernel, specifically in the xfs_dqinode_metadir_create() function responsible for creating quota inode metadata directories. When xfs_metadir_create() fails, the code path returns immediately without invoking xfs_metadir_cancel(), leaving the allocated 'update' and transaction state unreleased - a classic missing-release-after-effective-lifetime defect (CWE-401). A secondary leak path occurs when the subsequent commit fails: the caller-owned inode reference is never released. The bug was introduced at commit e80fbe1ad8eff7d7d1363e14f1e493d84dd37c84 and affects any kernel where the metadir XFS feature is present. The fix mirrors the existing unwind pattern in xfs_metadir_mkdir() by routing both failure paths through xfs_metadir_cancel() and explicitly releasing returned inode references. Affected CPE: cpe:2.3:a:linux:linux:*:*:*:*:*:*:*:*.

RemediationAI

Update to a patched Linux kernel release: 6.18.39 or 7.1.4 for stable-track systems, or 7.2-rc2 for mainline tracking. Fix commits are available at https://git.kernel.org/stable/c/c3d3d2212c2966973dd7d603c6c6e6ed6fc7fbe1, https://git.kernel.org/stable/c/45de375b25060edf46e20abb36521ba530336ceb, and https://git.kernel.org/stable/c/06a2e6dbaa26c0740ac76dfa66b0aedc78d05820. If an immediate kernel upgrade is not feasible, avoid mounting XFS filesystems with the user quota option (mount -o uquota) on metadir-capable images, which avoids executing the vulnerable code path; note that this workaround disables user quota enforcement. Systems not using XFS or not using metadir XFS with user quotas are not exposed.

Vendor StatusVendor

SUSE

Severity: Moderate
Product Status
openSUSE Tumbleweed Fixed
SUSE Linux Enterprise Desktop 15 SP7 Not-Affected
SUSE Linux Enterprise Desktop 15 SP7 Not-Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 Not-Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 Not-Affected

Share

CVE-2026-64356 vulnerability details – vuln.today

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy