Kernel crash via premature NAPI ID access
Published Sep 15, 2025 · Updated Sep 15, 2025
NULL-pointer dereference in Linux kernel AF_XDP transmit handling allows local users to crash the kernel through sendmsg() on a down interface. __xsk_sendmsg() marks the NAPI ID before xsk_xmit() checks IFF_UP, causing access through a NULL transmit-path pointer when the interface is not up. Exploitation requires low-privileged local access and a bound AF_XDP socket, and the demonstrated consequence is a kernel oops that interrupts availability.
Summary
What happened
NULL-pointer dereference in Linux kernel AF_XDP transmit handling allows local users to crash the kernel through sendmsg() on a down interface. __xsk_sendmsg() marks the NAPI ID before xsk_xmit() checks IFF_UP, causing access through a NULL transmit-path pointer when the interface is not up. Exploitation requires low-privileged local access and a bound AF_XDP socket, and the demonstrated consequence is a kernel oops that interrupts availability.
The record
- CVE
- CVE-2023-53240
- Published
- Sep 15, 2025
- Updated
- Sep 15, 2025
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-476, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 15, 2025CVE publishedPublication date reported by the CVE source.
- Sep 15, 2025Record updatedLatest update available in the CVE record.
Exploitability
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- Affected versionversion=18b1ab7aa76bde181bdb1ab19a87fa9523c32f21 <1596dae2f17ec5c6e8c8f0e3fec78c5ae55c1e0b
- Affected versionversion=18b1ab7aa76bde181bdb1ab19a87fa9523c32f21 <cecc68559cd57fffb2be50685f262b9af2318e16
- Affected versionversion=18b1ab7aa76bde181bdb1ab19a87fa9523c32f21 <ffe19750e68d0bb21e8110b398346eef20b156a7
- Affected versionversion=5.18
- Affected versionversion=8a2dea162b92c322f3e42eae0c4a74b8d20aa7a9
- Affected versionversion=ad7219cd8751bd258b9d1e69ae0654ec00f71875
- Affected versionversion=d1579253ffce39986e7a6ab757ac93b2680a665f
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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