Linux Kernel up to 5.12.2 cifs smb2_get_enc_key privilege escalation

Summaryinfo

A vulnerability classified as problematic was found in Linux Kernel up to 5.12.2. This issue affects the function smb2_get_enc_key of the component cifs. The manipulation results in an unknown weakness. This vulnerability is known as CVE-2021-46960. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.12.2 (Operating System). It has been classified as problematic. Affected is the function smb2_get_enc_key of the component cifs. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: cifs: Return correct error code from smb2_get_enc_key Avoid a warning if the error percolates back up: [440700.376476] CIFS VFS: \\otters.example.com crypt_message: Could not get encryption key [440700.386947] ------------[ cut here ]------------ [440700.386948] err = 1 [440700.386977] WARNING: CPU: 11 PID: 2733 at /build/linux-hwe-5.4-p6lk6L/linux-hwe-5.4-5.4.0/lib/errseq.c:74 errseq_set+0x5c/0x70 ... [440700.397304] CPU: 11 PID: 2733 Comm: tar Tainted: G OE 5.4.0-70-generic #78~18.04.1-Ubuntu ... [440700.397334] Call Trace: [440700.397346] __filemap_set_wb_err+0x1a/0x70 [440700.397419] cifs_writepages+0x9c7/0xb30 [cifs] [440700.397426] do_writepages+0x4b/0xe0 [440700.397444] __filemap_fdatawrite_range+0xcb/0x100 [440700.397455] filemap_write_and_wait+0x42/0xa0 [440700.397486] cifs_setattr+0x68b/0xf30 [cifs] [440700.397493] notify_change+0x358/0x4a0 [440700.397500] utimes_common+0xe9/0x1c0 [440700.397510] do_utimes+0xc5/0x150 [440700.397520] __x64_sys_utimensat+0x88/0xd0

The weakness was published 02/27/2024. The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2021-46960. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 225804 (RHEL 8 : kernel (RHSA-2025:2265)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.14.233, 4.19.191, 5.4.118, 5.10.36, 5.11.20, 5.12.3 or 5.13 eliminates this vulnerability. Applying the patch e94851629c49/e486f8397f3f/93f3339b22ba/aaa0faa5c28a/f59a9242942f/b399c1a3ea0b/83728cbf366e 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 vulnerability database at Tenable (225804). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.14.232
• 4.19.190
• 5.0
• 5.1
• 5.2
• 5.3
• 5.4
• 5.4.117
• 5.5
• 5.6
• 5.7
• 5.8
• 5.9
• 5.10
• 5.10.0
• 5.10.1
• 5.10.2
• 5.10.3
• 5.10.4
• 5.10.5
• 5.10.6
• 5.10.7
• 5.10.8
• 5.10.9
• 5.10.10
• 5.10.11
• 5.10.12
• 5.10.13
• 5.10.14
• 5.10.15
• 5.10.16
• 5.10.17
• 5.10.18
• 5.10.19
• 5.10.20
• 5.10.21
• 5.10.22
• 5.10.23
• 5.10.24
• 5.10.25
• 5.10.26
• 5.10.27
• 5.10.28
• 5.10.29
• 5.10.30
• 5.10.31
• 5.10.32
• 5.10.33
• 5.10.34
• 5.10.35
• 5.11
• 5.11.0
• 5.11.1
• 5.11.2
• 5.11.3
• 5.11.4
• 5.11.5
• 5.11.6
• 5.11.7
• 5.11.8
• 5.11.9
• 5.11.10
• 5.11.11
• 5.11.12
• 5.11.13
• 5.11.14
• 5.11.15
• 5.11.16
• 5.11.17
• 5.11.18
• 5.11.19
• 5.12
• 5.12.0
• 5.12.1
• 5.12.2

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

Once again VulDB remains the best source for vulnerability data.

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