Service exhaustion via leaked lockd file references
Published Aug 15, 2026 · Updated Aug 15, 2026
Resource leak in Linux kernel lockd allows remote authenticated users to exhaust file references through repeated failed cached opens. The cached-file path in nlm_lookup_file() increments file->f_count and assigns *result after nlm_do_fopen() fails, but its wrappers return without propagating the pointer, so nlm_release_file() never runs. Repeated requests keep hashed nlm_file records referenced and prevent nlm_traverse_files() from reaping them, consuming kernel resources without a reported confidentiality or integrity effect.
Summary
What happened
Resource leak in Linux kernel lockd allows remote authenticated users to exhaust file references through repeated failed cached opens. The cached-file path in nlm_lookup_file() increments file->f_count and assigns *result after nlm_do_fopen() fails, but its wrappers return without propagating the pointer, so nlm_release_file() never runs. Repeated requests keep hashed nlm_file records referenced and prevent nlm_traverse_files() from reaping them, consuming kernel resources without a reported confidentiality or integrity effect.
The record
- CVE
- CVE-2026-72218
- Published
- Aug 15, 2026
- Updated
- Aug 15, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499.004
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 15, 2026CVE publishedPublication date reported by the CVE source.
- Aug 15, 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=5.10.220 <5.10.261
- Affected versionversion=5.15
- Affected versionversion=7f024fcd5c97dc70bb9121c80407cf3cf9be7159 <3a5c55a19cad62f2973be25fe96a1a9e7f618e8a
- Affected versionversion=7f024fcd5c97dc70bb9121c80407cf3cf9be7159 <46d59ff421824b6483549d87f14efffbbbd1f6cb
- Affected versionversion=7f024fcd5c97dc70bb9121c80407cf3cf9be7159 <70a38f87bed7f0694fd07988b47b2db1e10d8df3
- Affected versionversion=7f024fcd5c97dc70bb9121c80407cf3cf9be7159 <7ce4c23e783e766507b2cef27bbf97e9ca944f1a
- Affected versionversion=7f024fcd5c97dc70bb9121c80407cf3cf9be7159 <84008bf1860e0ef8059a7583a1163f36b704d08a
- Affected versionversion=7f024fcd5c97dc70bb9121c80407cf3cf9be7159 <cb3420c047957e565101585bb4f15e1a6e3de6b0
- Affected versionversion=7f024fcd5c97dc70bb9121c80407cf3cf9be7159 <fe3b45b56b6c3d4b6b341de27fa291005287a21c
- Affected versionversion=e580323ac0b51ad10ec2e181d1f777479b7983e7 <6cd84cefd8b73e85b9eda17b319bd40a670f3a38
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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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