Out-of-bounds read via unterminated sysctl buffer
Published Sep 24, 2026 · Updated Sep 24, 2026
An out-of-bounds read in Linux 6.12 before 6.12.111 and 6.18 before 6.18.53 allows local users to read past a sysctl buffer. The bpf_sysctl_set_new_value helper copies buf_len bytes into ctx->new_val but fails to append the NUL terminator expected by downstream proc handlers. Reaching the faulty path requires a cgroup/sysctl BPF program and permission to replace a pending sysctl value; the demonstrated consequence is a KASAN-detected slab read beyond the 4,096-byte allocation.
Summary
What happened
An out-of-bounds read in Linux 6.12 before 6.12.111 and 6.18 before 6.18.53 allows local users to read past a sysctl buffer. The bpf_sysctl_set_new_value helper copies buf_len bytes into ctx->new_val but fails to append the NUL terminator expected by downstream proc handlers. Reaching the faulty path requires a cgroup/sysctl BPF program and permission to replace a pending sysctl value; the demonstrated consequence is a KASAN-detected slab read beyond the 4,096-byte allocation.
The record
- CVE
- CVE-2026-97420
- Published
- Sep 24, 2026
- Updated
- Sep 24, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Sep 24, 2026CVE publishedPublication date reported by the CVE source.
- Sep 24, 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=0 <6.12.111
- Affected versionversion=0 <6.18.53
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3b2814dd842a565fcf9cc370156e1ba9eae16239
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <76c14b10f50eb0afcc76e244562fa2d8c661e224
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a66e3b5bacf38d6ab29fa05a9754f7a114485605
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
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Technologies
Your stack
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Your stack
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