Local kernel information leak via uninitialized rseq field
Published Jun 25, 2026 · Updated Jun 25, 2026
Use of an uninitialized stack variable in Linux Kernel 7.0.10 through 7.0.12 allows local users to disclose kernel memory via rseq. In rseq_exit_user_update(), indeterminate initializer ordering lets node_id read ids.cpu_id before task_cpu(t) assigns it. Local low-privileged access is required, and the public record does not identify the exposed bytes or demonstrate broader impact.
Summary
What happened
Use of an uninitialized stack variable in Linux Kernel 7.0.10 through 7.0.12 allows local users to disclose kernel memory via rseq. In rseq_exit_user_update(), indeterminate initializer ordering lets node_id read ids.cpu_id before task_cpu(t) assigns it. Local low-privileged access is required, and the public record does not identify the exposed bytes or demonstrate broader impact.
The record
- CVE
- CVE-2026-53243
- Published
- Jun 25, 2026
- Updated
- Jun 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-908
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 25, 2026CVE publishedPublication date reported by the CVE source.
- Jun 25, 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=7.0.10 <7.0.13
- Affected versionversion=82f572449cfe75f12ea985986da60e11f308f77d <6d99479799c69c3cb588fcda19c81d8f61d64ecd
- Affected versionversion=d242126fd21ab8f1631fdbc8589e43a9d4229f3b <e12d20a63b61aaf9de4772effccf42cc9a003e58
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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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