Linux Kernel up to 6.12.35/6.15.4 io_uring privilege escalation

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.12.35/6.15.4. The affected element is an unknown function of the component io_uring. Performing a manipulation results in an unknown weakness. This vulnerability was named CVE-2025-40216. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.12.35/6.15.4. This affects some unknown processing of the component io_uring. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: io_uring/rsrc: don't rely on user vaddr alignment There is no guaranteed alignment for user pointers, however the calculation of an offset of the first page into a folio after coalescing uses some weird bit mask logic, get rid of it.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-40216 since 04/16/2025. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 02/23/2026).

The vulnerability scanner Nessus provides a plugin with the ID 277593 (Linux Distros Unpatched Vulnerability : CVE-2025-40216), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.36 or 6.15.5 eliminates this vulnerability. Applying the patch 50998b0ae7d9d552e96d8b7239981cf05f65eff5/f16769241594be59387b56ab525e327f54377e60/3a3c6d61577dbb23c09df3e21f6f9eda1ecd634b 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 (277593) and CERT Bund (WID-SEC-2025-2747). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Debian Linux
• Google Cloud Platform
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Microsoft Azure Linux

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.15.0
• 6.15.1
• 6.15.2
• 6.15.3
• 6.15.4

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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

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