#VU80497 Off-by-one in Linux kernel - CVE-2023-38429

Vulnerability identifier: #VU80497

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2023-38429

CWE-ID: CWE-193

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to an off-by-one error within the ksmbd_smb2_check_message() function in fs/ksmbd/connection.c. A remote attacker can trigger an off-by-one error and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 6.3.4, 6.3.4

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External links
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/fs/ksmbd?id=443d61d1fa9faa60ef925513d83742902390100f
https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.3.4

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.