Local privilege escalation via stale NFQUEUE references
Published May 5, 2026 · Updated May 5, 2026
Use-after-free in the Linux Kernel nft_ct module allows local users to gain kernel privileges through nftables and NFQUEUE operations. Pending NFQUEUE packets retain references to conntrack zone templates, timeout policies, or helpers after nft_ct destroys those objects, and verdict reinjection dereferences freed kernel memory. Reaching the flaw requires CAP_NET_ADMIN in the target network namespace; user and network namespaces can expose that capability, and exploitation can disclose or modify kernel memory or crash the host.
Summary
What happened
Use-after-free in the Linux Kernel nft_ct module allows local users to gain kernel privileges through nftables and NFQUEUE operations. Pending NFQUEUE packets retain references to conntrack zone templates, timeout policies, or helpers after nft_ct destroys those objects, and verdict reinjection dereferences freed kernel memory. Reaching the flaw requires CAP_NET_ADMIN in the target network namespace; user and network namespaces can expose that capability, and exploitation can disclose or modify kernel memory or crash the host.
The record
- CVE
- CVE-2026-43060
- Published
- May 5, 2026
- Updated
- May 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 5, 2026CVE publishedPublication date reported by the CVE source.
- May 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=4.19
- Affected versionversion=7e0b2b57f01d183e1c84114f1f2287737358d748 <36eae0956f659e48d5366d9b083d9417f3263ddc
- Affected versionversion=7e0b2b57f01d183e1c84114f1f2287737358d748 <3da0b946835f33bf36b459ead764c61a761e689b
- Affected versionversion=7e0b2b57f01d183e1c84114f1f2287737358d748 <6802ff8beceb9c4254318e81c1395720438f2cc2
- Affected versionversion=7e0b2b57f01d183e1c84114f1f2287737358d748 <77da55dee67720e2b8d2db49a53334e6c017ee7b
- Affected versionversion=7e0b2b57f01d183e1c84114f1f2287737358d748 <8a64e76933672b08bd85b63086f33432070fd729
- Affected versionversion=7e0b2b57f01d183e1c84114f1f2287737358d748 <ab50302190b303f847c4eba0e31a01a56dec596e
- Affected versionversion=7e0b2b57f01d183e1c84114f1f2287737358d748 <e68a8db3a0546482b34e9ca5ca886bcf73eb37bb
- Affected versionversion=7e0b2b57f01d183e1c84114f1f2287737358d748 <f29a055e4f593e577805b41228b142b58f48df1b
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Technologies
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Your stack
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