CVE-2026-63954

Received Received - Intake

HPFS filesystem crash due to uninitialized buffer head

Publication date: 2026-07-19

Last updated on: 2026-07-20

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: hpfs: fix a crash if hpfs_map_dnode_bitmap fails If hpfs_map_dnode_bitmap fails, the code would call hpfs_brelse4 on uninitialized quad buffer head, causing a crash.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-07-19

Last Modified

2026-07-20

Generated

2026-07-20

AI Q&A

2026-07-19

EPSS Evaluated

N/A

NVD

CVE-2026-63954

EUVD

EUVD-2026-45727

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability is in the Linux kernel's HPFS (High Performance File System) driver. It occurs when the function hpfs_map_dnode_bitmap fails, leading to an attempt to release an uninitialized buffer head via hpfs_brelse4, which causes a system crash.

Detection Guidance

This vulnerability is specific to the Linux kernel's HPFS filesystem handling. Detection requires checking for kernel crashes or errors related to hpfs_map_dnode_bitmap failures. Monitor system logs for filesystem errors or kernel panics. No direct commands are provided in the context to detect this issue.

Impact Analysis

If exploited, this vulnerability could crash the affected system, leading to denial of service. Users relying on HPFS for file storage may experience unexpected system failures.

Compliance Impact

This vulnerability causes a kernel crash due to improper handling of a failed bitmap mapping in the HPFS filesystem. It does not directly relate to data privacy, access controls, or audit logging required by standards like GDPR or HIPAA. The impact is primarily system stability rather than compliance violations.

Mitigation Strategies

Apply the latest Linux kernel patches that address this issue. If using a vulnerable kernel version, avoid mounting or using HPFS filesystems until patched. Monitor vendor advisories for updates.

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