Kernel memory faults via premature BTF release
Published Oct 18, 2026 · Updated Oct 18, 2026
Use-after-free in Linux BPF map teardown allows local users to trigger kernel memory faults by freeing populated hash maps. The bpf_ma_set_dtor() function duplicates a destructor record without retaining its map BTF, leaving deferred cleanup workers to dereference freed metadata. Triggering requires access to affected BPF map operations and deferred RCU cleanup; the published evidence demonstrates invalid kernel reads, not privilege escalation.
Summary
What happened
Use-after-free in Linux BPF map teardown allows local users to trigger kernel memory faults by freeing populated hash maps. The bpf_ma_set_dtor() function duplicates a destructor record without retaining its map BTF, leaving deferred cleanup workers to dereference freed metadata. Triggering requires access to affected BPF map operations and deferred RCU cleanup; the published evidence demonstrates invalid kernel reads, not privilege escalation.
The record
- CVE
- CVE-2026-98813
- Published
- Oct 18, 2026
- Updated
- Oct 18, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Oct 18, 2026CVE publishedPublication date reported by the CVE source.
- Oct 18, 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=1df97a7453eec80c1912c2d0360290a3970a7671 <ab39974240a0cff765f3bb9cce81d8001ffdb144
- Affected versionversion=1df97a7453eec80c1912c2d0360290a3970a7671 <b506f5699e145196ee29d76cf1ca1cbb2202c055
- Affected versionversion=451a84a3ad3c897c03181af433e7c98640730f1f
- Affected versionversion=51a17f0ce19c4ee2a25cf16c93490d509b1ebb0a
- Affected versionversion=6.12.112 <6.13
- Affected versionversion=6.18.55 <6.19
- Affected versionversion=7.0
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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