CVE-2026-72202

Received Received - Intake

Heap Allocation Failure in Linux Kernel NTFS

Publication date: 2026-08-15

Last updated on: 2026-08-18

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: ntfs: avoid heap allocation for free-cluster readahead state get_nr_free_clusters() allocates a temporary file_ra_state before it publishes the precomputed free cluster count, sets NVolFreeClusterKnown(), and wakes vol->free_waitq. If that allocation fails, the worker returns without setting the flag or waking waiters, so callers waiting for the free count can block indefinitely. The readahead state is only used synchronously while scanning the bitmap. Keep it on the stack and pass it by address to the readahead helper. This eliminates the early allocation failure path instead of adding a special case that publishes a conservative count and wakes the waitqueue. Zero-initialize the on-stack state because file_ra_state_init() only sets ra_pages and prev_pos. Apply the same treatment to __get_nr_free_mft_records(), which scans the MFT bitmap with the same short-lived readahead state.

CVSS Scores

EPSS Scores

Probability:
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Meta Information

Published

2026-08-15

Last Modified

2026-08-18

Generated

2026-09-04

AI Q&A

2026-08-15

EPSS Evaluated

2026-09-03

NVD

CVE-2026-72202

EUVD

EUVD-2026-58960

Affected Vendors & Products

Vendor	Product	Version / Range
linux_kernel	linux_kernel	*
linux	kernel	*
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability in the Linux kernel involves a potential indefinite blocking issue in the NTFS file system. The function get_nr_free_clusters() allocates memory for a temporary state before completing its task. If this allocation fails, the function exits without setting a flag or waking up waiting processes, causing them to block indefinitely.

Detection Guidance

This vulnerability is specific to the Linux kernel's NTFS implementation and may not have direct detection commands. Monitor for kernel crashes or hangs during NTFS operations, especially when accessing large filesystems. Check kernel logs for errors related to ntfs or free cluster calculations.

Impact Analysis

This vulnerability could cause system hangs or delays when accessing NTFS volumes. Processes waiting for free cluster counts may freeze indefinitely, disrupting normal operations and potentially leading to system instability or unresponsiveness.

Compliance Impact

This vulnerability does not directly affect compliance with GDPR, HIPAA, or similar standards. It is a Linux kernel issue related to heap allocation failure in NTFS file system operations, causing potential indefinite blocking of callers waiting for free cluster counts. No data exposure or privacy implications are described.

Mitigation Strategies

Update your Linux kernel to the latest stable version that includes the fix for CVE-2026-72202. Avoid using NTFS filesystems until patched. If NTFS is required, consider temporary alternatives or restrict access to untrusted users.

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