Local process termination via unbalanced page-fault handling
Published Dec 27, 2024 · Updated May 23, 2026
Denial of service in Linux kernel 6.9.4 through 6.12.3 allows local users to kill a process during s390 user stack walking. When store_ip() fails in arch_stack_walk_user_common(), an early return bypasses pagefault_enable(), so later page faults are not handled. Exploitation requires local low-privileged access and an s390 system performing a user-space stack walk; the impact is limited to termination of the affected process.
Summary
What happened
Denial of service in Linux kernel 6.9.4 through 6.12.3 allows local users to kill a process during s390 user stack walking. When store_ip() fails in arch_stack_walk_user_common(), an early return bypasses pagefault_enable(), so later page faults are not handled. Exploitation requires local low-privileged access and an s390 system performing a user-space stack walk; the impact is limited to termination of the affected process.
The record
- CVE
- CVE-2024-56550
- Published
- Dec 27, 2024
- Updated
- May 23, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Dec 27, 2024CVE publishedPublication date reported by the CVE source.
- May 23, 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?
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- Affected versionversion=6.10
- Affected versionversion=6.9.4 <6.10
- Affected versionversion=dd69165ac3dc12d8550aeec3fc4439c084ded3d8
- Affected versionversion=ebd912ff9919a10609511383d94942362234c077 <20c26357826457dc7c8145297e60ddc012e18914
- Affected versionversion=ebd912ff9919a10609511383d94942362234c077 <588a9836a4ef7ec3bfcffda526dfa399637e6cfc
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
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Technologies
Your stack
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Your stack
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