Linux Kernel up to 6.1.113/6.6.57/6.11.4 ksmbd session_lock use after free

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.1.113/6.6.57/6.11.4 and classified as critical. This vulnerability affects the function session_lock of the component ksmbd. Performing a manipulation results in use after free. This vulnerability is known as CVE-2024-50086. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.1.113/6.6.57/6.11.4. This affects the function session_lock of the component ksmbd. 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. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix user-after-free from session log off There is racy issue between smb2 session log off and smb2 session setup. It will cause user-after-free from session log off. This add session_lock when setting SMB2_SESSION_EXPIRED and referece count to session struct not to free session while it is being used.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2024-50086 since 10/21/2024. 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 08/21/2025).

The vulnerability scanner Nessus provides a plugin with the ID 213191 (Oracle Linux 8 / 9 : Unbreakable Enterprise kernel (ELSA-2024-12887)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.114, 6.6.58 or 6.11.5 eliminates this vulnerability. Applying the patch a9839c37fd81/5511999e9615/ee371898b53a/7aa8804c0b67 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 (213191) and CERT Bund (WID-SEC-2024-3289). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• Open Source eCryptfs
• NetApp ActiveIQ Unified Manager
• SUSE openSUSE
• RESF Rocky Linux
• IBM QRadar SIEM

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.113
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.6.44
• 6.6.45
• 6.6.46
• 6.6.47
• 6.6.48
• 6.6.49
• 6.6.50
• 6.6.51
• 6.6.52
• 6.6.53
• 6.6.54
• 6.6.55
• 6.6.56
• 6.6.57
• 6.11.0
• 6.11.1
• 6.11.2
• 6.11.3
• 6.11.4

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

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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