Kernel warning via invalid BTF return type
Published Dec 30, 2025 · Updated Dec 30, 2025
Improper BTF validation in Linux kernel 5.15 through 6.0.6 allows local users to trigger a kernel warning through crafted BTF metadata. The btf_func_proto_check function accepts a BTF_KIND_DECL_TAG record as a function-prototype return type, causing btf_type_id_size to reach its warning path while resolving the invalid type. Reaching BPF_BTF_LOAD requires CAP_SYS_ADMIN; the published reproducer reports a warning, not a crash or code execution.
Summary
What happened
Improper BTF validation in Linux kernel 5.15 through 6.0.6 allows local users to trigger a kernel warning through crafted BTF metadata. The btf_func_proto_check function accepts a BTF_KIND_DECL_TAG record as a function-prototype return type, causing btf_type_id_size to reach its warning path while resolving the invalid type. Reaching BPF_BTF_LOAD requires CAP_SYS_ADMIN; the published reproducer reports a warning, not a crash or code execution.
The record
- CVE
- CVE-2022-50862
- Published
- Dec 30, 2025
- Updated
- Dec 30, 2025
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Dec 30, 2025CVE publishedPublication date reported by the CVE source.
- Dec 30, 2025Record 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=5.16
- Affected versionversion=bd16dee66ae4de3f1726c69ac901d2b7a53b0c86 <e9dbb4c539d058852b76937dcd7347d3f38054f2
- Affected versionversion=bd16dee66ae4de3f1726c69ac901d2b7a53b0c86 <ea68376c8bed5cd156900852aada20c3a0874d17
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.
Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
- Linux BPF decl_tag return-type reproducerproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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