Local privilege escalation via freed catch-all traversal
Published Mar 4, 2024 · Updated Aug 5, 2026
Use-after-free in Linux kernel 5.13 through 5.15.11 and 5.16 release candidates allows local users to escalate privileges. nft_set_catchall_destroy traverses catch-all elements with a non-safe list iterator and accesses the current entry after kfree_rcu() schedules it for freeing. Local syscall access with CAP_NET_ADMIN in a network namespace is required; exploitation enables kernel code execution, memory access, or a kernel crash.
Summary
What happened
Use-after-free in Linux kernel 5.13 through 5.15.11 and 5.16 release candidates allows local users to escalate privileges. nft_set_catchall_destroy traverses catch-all elements with a non-safe list iterator and accesses the current entry after kfree_rcu() schedules it for freeing. Local syscall access with CAP_NET_ADMIN in a network namespace is required; exploitation enables kernel code execution, memory access, or a kernel crash.
The record
- CVE
- CVE-2021-47106
- Published
- Mar 4, 2024
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-416, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 4, 2024CVE publishedPublication date reported by the CVE source.
- Aug 5, 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=5.13
- Affected versionversion=aaa31047a6d25da0fa101da1ed544e1247949b40 <0f7d9b31ce7abdbb29bf018131ac920c9f698518
- Affected versionversion=aaa31047a6d25da0fa101da1ed544e1247949b40 <9d558e5f0d6fdd0a568f73dceb0b40c4f5012e5a
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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Public exploit references
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Technologies
Your stack
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Your stack
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