CVE-2023-32248: Linux Kernel ksmbd Tree Connection NULL Pointer Dereference Denial-of-Service Vulnerability
A flaw was found in the Linux kernel's ksmbd, a high-performance in-kernel SMB server. The specific flaw exists within the handling of SMB2TREECONNECT and SMB2QUERYINFO commands. The issue results from the lack of proper validation of a pointer prior to accessing it. An attacker can leverage this vulnerability to create a denial-of-service condition on the system.
Other sources
A NULL pointer dereference issue was found in ksmbd, a high-performance in-kernel SMB server. Quoting ZDI security advisory [1]:
"This vulnerability allows remote attackers to create a denial-of-service condition on affected installations of Linux Kernel. Authentication is not required to exploit this vulnerability, but only systems with ksmbd enabled are vulnerable.
The specific flaw exists within the handling of SMB2TREECONNECT and SMB2QUERYINFO commands. The issue results from the lack of proper validation of a pointer prior to accessing it. An attacker can leverage this vulnerability to create a denial-of-service condition on the system."
[1] https://www.zerodayinitiative.com/advisories/ZDI-CAN-20479/
— Red Hat
Affected Software
Remediation
Patch Available
Patch Available
Event History
Frequently Asked Questions
What is the severity of CVE-2023-32248?
CVE-2023-32248 has a medium severity rating due to its exploitation potential affecting the Linux kernel's ksmbd.
How do I fix CVE-2023-32248?
To mitigate CVE-2023-32248, update your Linux kernel to version 6.4 or later, or to the fixed versions if using the Debian Linux package.
Which Linux kernel versions are affected by CVE-2023-32248?
CVE-2023-32248 affects Linux kernel versions from 5.15 up to 6.3.9 but is resolved in version 6.4 and subsequent releases.
What components are affected by CVE-2023-32248?
CVE-2023-32248 specifically impacts the ksmbd component in the Linux kernel, which functions as an in-kernel SMB server.
Is CVE-2023-32248 remotely exploitable?
Yes, CVE-2023-32248 can be exploited remotely due to improper validation of pointers within SMB commands.