Soft lockups via unbounded checkpoint-list scans
Published Sep 11, 2026 · Updated Sep 11, 2026
Denial of service in Linux kernel jbd2 allows attackers to trigger soft lockups during checkpoint-list shrinking in affected releases. journal_shrink_one_cp_list charges nr_to_scan only for checkpoint buffers it releases, so busy buffers permit a full-list scan while journal->j_list_lock stays held. The path requires a large checkpoint transaction dominated by busy buffers; contending CPUs can spin until a soft lockup or RCU stall interrupts service.
Summary
What happened
Denial of service in Linux kernel jbd2 allows attackers to trigger soft lockups during checkpoint-list shrinking in affected releases. journal_shrink_one_cp_list charges nr_to_scan only for checkpoint buffers it releases, so busy buffers permit a full-list scan while journal->j_list_lock stays held. The path requires a large checkpoint transaction dominated by busy buffers; contending CPUs can spin until a soft lockup or RCU stall interrupts service.
The record
- CVE
- CVE-2026-89567
- Published
- Sep 11, 2026
- Updated
- Sep 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499.004
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 11, 2026CVE publishedPublication date reported by the CVE source.
- Sep 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=5.15.129 <5.16
- Affected versionversion=557fda9ed70ebf8eda2620ba3d746215285a1303
- Affected versionversion=5fda50e262e65bd553ff777c4b280afd1495a18b
- Affected versionversion=6.1.50 <6.2
- Affected versionversion=6.4.13 <6.5
- Affected versionversion=6.5
- Affected versionversion=9c31bb2684f8035beca0275349d19d679b679ffb
- Affected versionversion=b98dba273a0e47dbfade89c9af73c5b012a4eabb <15cb16496446b94e67f7abcb049b8e2c75cd3d02
- Affected versionversion=b98dba273a0e47dbfade89c9af73c5b012a4eabb <71c6b872c746465fa4b5def239cb296173ca8216
- Affected versionversion=b98dba273a0e47dbfade89c9af73c5b012a4eabb <c2c0fb364685b8996c357d3b050394959b29d6e0
- Affected versionversion=b98dba273a0e47dbfade89c9af73c5b012a4eabb <edf5fcd0469b7467bd5b37a79502c8d9c3257dbb
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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