Linux Kernel up to 6.17.12/6.18.1 _set_reqsize memory corruption

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel up to 6.17.12/6.18.1. This impacts the function _set_reqsize. Performing a manipulation results in memory corruption. This vulnerability was named CVE-2025-68726. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.17.12/6.18.1. This affects the function _set_reqsize. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: crypto: aead - Fix reqsize handling Commit afddce13ce81d ("crypto: api - Add reqsize to crypto_alg") introduced cra_reqsize field in crypto_alg struct to replace type specific reqsize fields. It looks like this was introduced specifically for ahash and acomp from the commit description as subsequent commits add necessary changes in these alg frameworks. However, this is being recommended for use in all crypto algs instead of setting reqsize using crypto_*_set_reqsize(). Using cra_reqsize in aead algorithms, hence, causes memory corruptions and crashes as the underlying functions in the algorithm framework have not been updated to set the reqsize properly from cra_reqsize. [1] Add proper set_reqsize calls in the aead init function to properly initialize reqsize for these algorithms in the framework. [1]: https://gist.github.com/Pratham-T/24247446f1faf4b7843e4014d5089f6b

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-68726 since 12/24/2025. The exploitability is told to be easy. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 12/28/2025).

The vulnerability scanner Nessus provides a plugin with the ID 279792 (Linux Distros Unpatched Vulnerability : CVE-2025-68726), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.17.13, 6.18.2 or 6.19-rc1 eliminates this vulnerability. Applying the patch 64377e66e187164bd6737112d07257f5f0feb681/12b413f5460c393d1151a37f591140693eca0f84/9b04d8f00569573796dd05397f5779135593eb24 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 (279792) and CERT Bund (WID-SEC-2025-2920). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Open Source Linux Kernel

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.17.0
• 6.17.1
• 6.17.2
• 6.17.3
• 6.17.4
• 6.17.5
• 6.17.6
• 6.17.7
• 6.17.8
• 6.17.9
• 6.17.10
• 6.17.11
• 6.17.12
• 6.18.0
• 6.18.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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