Uninitialized-value use via malformed HFS+ node size
Published Aug 28, 2026 · Updated Aug 28, 2026
Improper validation in Linux 7.1 allows local users to trigger uninitialized-value use by mounting a corrupted HFS+ image. The HFS+ B-tree opener accepts a node_size of 1, causing hfs_bnode_find to pass an excessive record offset and leave its off variable uninitialized. The reproducer requires local mount privileges; upstream testing did not classify the condition as denial of service or exploitable.
Summary
What happened
Improper validation in Linux 7.1 allows local users to trigger uninitialized-value use by mounting a corrupted HFS+ image. The HFS+ B-tree opener accepts a node_size of 1, causing hfs_bnode_find to pass an excessive record offset and leave its off variable uninitialized. The reproducer requires local mount privileges; upstream testing did not classify the condition as denial of service or exploitable.
The record
- CVE
- CVE-2026-80656
- Published
- Aug 28, 2026
- Updated
- Aug 28, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Aug 28, 2026CVE publishedPublication date reported by the CVE source.
- Aug 28, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=7.1
- Affected versionversion=8ad2c6a36ac4328072377906a47ea0bff11e4032 <306265eb9384d2c224f1b14d83a29323f0eab6d1
- Affected versionversion=8ad2c6a36ac4328072377906a47ea0bff11e4032 <3f95e2661574ff13f099dd13456751933c280628
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
- syzbot C reproducer and malformed HFS+ imageproof of concept · validated
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Technologies
Your stack
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Your stack
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