CVE-2026-97551
Received Received - Intake

XFS Filesystem Parent Pointer Update Heap Overflow

Publication date: 2026-09-25

Last updated on: 2026-09-25

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: xfs: initialise args->total for parent pointer updates xfs_parent_da_args_init() builds an xfs_da_args from a zeroed xfs_parent_args (kmem_cache_zalloc), leaving args->total == 0. xfs_da_grow_inode_int() treats that field as a running block reservation and subtracts from it; because it is an xfs_extlen_t (uint32_t), the first attr-fork growth wraps it to ~0U. That defeats the free-space check in xfs_alloc_space_available(), and when it coincides with an AG that has exactly zero available blocks the allocation is clamped to maxlen 0 and returns -ENOSPC, which xfs_defer_finish_noroll() escalates to a filesystem shutdown. Set args->total the way the log recovery path does (xfs_attri_recover_work(), xfs_attr_item.c:706), in the add and replace paths that can grow the fork. Removals and lookups never grow it, so they leave the field alone, matching that switch.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-09-25
Last Modified
2026-09-25
Generated
2026-09-25
AI Q&A
2026-09-25
EPSS Evaluated
N/A
NVD
CVE-2026-97551
EUVD
EUVD-2026-86859

Affected Vendors & Products

Currently, no data is known.

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This is a Linux kernel vulnerability in the XFS filesystem. It occurs when initializing parent pointer updates where a field called args->total is left uninitialized (set to 0). This causes incorrect block reservation calculations during attribute fork growth, leading to filesystem shutdowns when free space checks fail.

Detection Guidance

This vulnerability is specific to the Linux kernel's XFS filesystem and does not have network-based detection methods. To check if your system is vulnerable, verify the kernel version and whether the XFS filesystem is in use. Commands like 'uname -a' and 'mount | grep xfs' can help identify the kernel and filesystem. If your kernel version is older than the patched version, the system may be vulnerable.

Impact Analysis

If exploited, this vulnerability could cause the XFS filesystem to crash or become unavailable, potentially leading to data loss or system downtime. Users relying on systems with XFS filesystems could experience unexpected shutdowns or corruption.

Mitigation Strategies

Apply the latest kernel update provided by your Linux distribution to patch the XFS vulnerability. If immediate patching is not possible, avoid using the XFS filesystem for critical operations until patched. Monitor filesystem logs for errors like ENOSPC or filesystem shutdown events, which may indicate exploitation attempts.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-97551. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart