Linux Kernel up to 6.15.9/6.16.0 fbnic queues.py __sk_mark_napi_id_once use after free

Summaryinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.15.9/6.16.0. This impacts the function __sk_mark_napi_id_once of the file queues.py of the component fbnic. The manipulation leads to use after free. This vulnerability is referenced as CVE-2025-38570. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.15.9/6.16.0. It has been rated as critical. This issue affects the function __sk_mark_napi_id_once of the file queues.py of the component fbnic. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: eth: fbnic: unlink NAPIs from queues on error to open CI hit a UaF in fbnic in the AF_XDP portion of the queues.py test. The UaF is in the __sk_mark_napi_id_once() call in xsk_bind(), NAPI has been freed. Looks like the device failed to open earlier, and we lack clearing the NAPI pointer from the queue.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2025-38570 since 04/16/2025. The exploitation is known to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 12/15/2025).

The vulnerability scanner Nessus provides a plugin with the ID 260177 (Linux Distros Unpatched Vulnerability : CVE-2025-38570), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.15.10, 6.16.1 or 6.17-rc1 eliminates this vulnerability. Applying the patch 21d3f8441c7f317b93ba6a8029610c8b7e3773db/4b59f9deff3bdb52b223c85048f1d2924803b817/4b31bcb025cb497da2b01f87173108ff32d350d2 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (260177) and CERT Bund (WID-SEC-2025-1869). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• RESF Rocky Linux
• Dell Avamar
• Open Source Linux Kernel
• Dell NetWorker
• Dell Secure Connect Gateway
• IBM QRadar SIEM

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.0
• 6.1
• 6.2
• 6.3
• 6.4
• 6.5
• 6.6
• 6.7
• 6.8
• 6.9
• 6.10
• 6.11
• 6.12
• 6.13
• 6.14
• 6.15
• 6.15.0
• 6.15.1
• 6.15.2
• 6.15.3
• 6.15.4
• 6.15.5
• 6.15.6
• 6.15.7
• 6.15.8
• 6.15.9
• 6.16.0

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Exploitinginfo

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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