Linux Kernel up to 6.12.1 SMB Client cifs_mount use after free

Summaryinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.12.1. This affects the function cifs_mount of the component SMB Client. This manipulation causes use after free. This vulnerability appears as CVE-2024-53179. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.12.1. Affected by this vulnerability is the function cifs_mount of the component SMB Client. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix use-after-free of signing key Customers have reported use-after-free in @ses->auth_key.response with SMB2.1 + sign mounts which occurs due to following race: task A task B cifs_mount() dfs_mount_share() get_session() cifs_mount_get_session() cifs_send_recv() cifs_get_smb_ses() compound_send_recv() cifs_setup_session() smb2_setup_request() kfree_sensitive() smb2_calc_signature() crypto_shash_setkey() *UAF* Fix this by ensuring that we have a valid @ses->auth_key.response by checking whether @ses->ses_status is SES_GOOD or SES_EXITING with @ses->ses_lock held. After commit 24a9799aa8ef ("smb: client: fix UAF in smb2_reconnect_server()"), we made sure to call ->logoff() only when @ses was known to be good (e.g. valid ->auth_key.response), so it's safe to access signing key when @ses->ses_status == SES_EXITING.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2024-53179 since 11/19/2024. The exploitation appears to be difficult. 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 12/14/2025).

The vulnerability scanner Nessus provides a plugin with the ID 214250 (SUSE SLES15 / openSUSE 15 Security Update : kernel (SUSE-SU-2025:0117-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.2 eliminates this vulnerability. Applying the patch 0e2b654a3848bf9da3b0d54c1ccf3f1b8c635591/343d7fe6df9e247671440a932b6a73af4fa86d95 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 (214250) and CERT Bund (WID-SEC-2024-3762). 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
• RESF Rocky Linux
• Dell NetWorker
• Dell Avamar
• Red Hat OpenShift
• IBM QRadar SIEM
• Dell PowerProtect Data Domain
• Open Source Linux Kernel
• IBM DataPower Gateway
• Dell Secure Connect Gateway

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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Entryinfo

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

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