Local kernel crash via uninitialized association mapping
Published Jul 12, 2024 · Updated May 11, 2026
NULL pointer dereference in Linux OCFS2 6.6 before 6.6.36 and 6.7 through 6.9.6 allows local users to crash the kernel. The ocfs2_journal_dirty() path dereferences b_assoc_map->host->i_sb before b_assoc_map is initialized when journal credits are exhausted. Exploitation requires local access to a mounted OCFS2 filesystem and a file-clone path that exhausts transaction credits; the resulting fault interrupts the host.
Summary
What happened
NULL pointer dereference in Linux OCFS2 6.6 before 6.6.36 and 6.7 through 6.9.6 allows local users to crash the kernel. The ocfs2_journal_dirty() path dereferences b_assoc_map->host->i_sb before b_assoc_map is initialized when journal credits are exhausted. Exploitation requires local access to a mounted OCFS2 filesystem and a file-clone path that exhausts transaction credits; the resulting fault interrupts the host.
The record
- CVE
- CVE-2024-40952
- Published
- Jul 12, 2024
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-476, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 12, 2024CVE publishedPublication date reported by the CVE source.
- May 11, 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=6.6
- Affected versionversion=8887b94d93224e0ef7e1bc6369640e313b8b12f4 <0550ad87711f815b3d73e487ec58ca7d8f56edbc
- Affected versionversion=8887b94d93224e0ef7e1bc6369640e313b8b12f4 <58f7e1e2c9e72c7974054c64c3abeac81c11f822
- Affected versionversion=8887b94d93224e0ef7e1bc6369640e313b8b12f4 <72663d3e09091f431a0774227ca207c0358362dd
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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