Kernel read and write via kptr type confusion
Published Sep 25, 2026 · Updated Sep 25, 2026
Type confusion in the Linux kernel 6.7 allows attackers to obtain arbitrary kernel read and write via a crafted BPF program. map_kptr_match_type() treats MEM_PERCPU as a permitted flag instead of requiring it on values stored in __percpu_kptr fields, so the verifier accepts plain allocations and referenced kernel pointers. Reaching the flaw requires loading such a BPF program; later per-CPU relocation or teardown can access invalid kernel addresses or use the wrong destruction path.
Summary
What happened
Type confusion in the Linux kernel 6.7 allows attackers to obtain arbitrary kernel read and write via a crafted BPF program. map_kptr_match_type() treats MEM_PERCPU as a permitted flag instead of requiring it on values stored in __percpu_kptr fields, so the verifier accepts plain allocations and referenced kernel pointers. Reaching the flaw requires loading such a BPF program; later per-CPU relocation or teardown can access invalid kernel addresses or use the wrong destruction path.
The record
- CVE
- CVE-2026-98039
- Published
- Sep 25, 2026
- Updated
- Sep 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1068
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 25, 2026CVE publishedPublication date reported by the CVE source.
- Sep 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?
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- Affected versionversion=36d8bdf75a93190e5669b9d1d95994e13e15ba1d <048029ba1c793f8cabc4ad5eea765da01903f8f1
- Affected versionversion=36d8bdf75a93190e5669b9d1d95994e13e15ba1d <0bdd6121c8dd5f1764efe701ce26bb8e15acb172
- Affected versionversion=36d8bdf75a93190e5669b9d1d95994e13e15ba1d <aaa9cf7707d1c5c0d2ca9d40c8b71652ac1c3c3f
- Affected versionversion=36d8bdf75a93190e5669b9d1d95994e13e15ba1d <ad4ebae5dbc2d47b544aa54f03c12490065be08a
- Affected versionversion=6.7
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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Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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