Linux Kernel up to 6.1.38/6.3.12/6.4.3 cifs smb2_compound_op use after free

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.38/6.3.12/6.4.3. It has been declared as critical. This affects the function smb2_compound_op of the component cifs. The manipulation results in use after free. This vulnerability is identified as CVE-2023-53377. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.1.38/6.3.12/6.4.3. Affected is the function smb2_compound_op of the component cifs. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: cifs: prevent use-after-free by freeing the cfile later In smb2_compound_op we have a possible use-after-free which can cause hard to debug problems later on. This was revealed during stress testing with KASAN enabled kernel. Fixing it by moving the cfile free call to a few lines below, after the usage.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2023-53377 since 09/17/2025. The exploitability is told to be easy. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 12/12/2025).

The vulnerability scanner Nessus provides a plugin with the ID 265602 (Linux Distros Unpatched Vulnerability : CVE-2023-53377), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.39, 6.3.13 or 6.4.4 eliminates this vulnerability. Applying the patch 4fe07d55a5461e66a55fbefb57f85ff0facea32b/b6353518ef8180816e863aa23b06456f395404d6/d017880782cf71f8820ee4a2002843893176501d/33f736187d08f6bc822117629f263b97d3df4165 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 (265602) and CERT Bund (WID-SEC-2025-2092). Once again VulDB remains the best source for vulnerability data.

Affected

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

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.1.25
• 6.1.26
• 6.1.27
• 6.1.28
• 6.1.29
• 6.1.30
• 6.1.31
• 6.1.32
• 6.1.33
• 6.1.34
• 6.1.35
• 6.1.36
• 6.1.37
• 6.1.38
• 6.3.0
• 6.3.1
• 6.3.2
• 6.3.3
• 6.3.4
• 6.3.5
• 6.3.6
• 6.3.7
• 6.3.8
• 6.3.9
• 6.3.10
• 6.3.11
• 6.3.12
• 6.4.0
• 6.4.1
• 6.4.2
• 6.4.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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