CVE-2023-52442 ksmbd: validate session id and tree id in compound request

What is CVE-2023-52442?

CVE-2023-52442 is a critical missing authorization vulnerability in Linux kernel, published on 21 Feb 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: validate session id and tree id in compound request

`smb2_get_msg()` in smb2_get_ksmbd_tcon() and smb2_check_user_session() will always return the first request smb2 header in a compound request. if `SMB2_TREE_CONNECT_HE` is the first command in compound request, will return 0, i.e. The tree id check is skipped. This patch use ksmbd_req_buf_next() to get current command in compound.

Which versions are affected by CVE-2023-52442?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-52442?

Apply the vendor's patch.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2023-52442 being exploited?

There is no known exploitation of CVE-2023-52442 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2023-52442, CVE-2023-39177, DEBIAN-CVE-2023-52442, GHSA-5wjx-fx3x-22c6, UBUNTU-CVE-2023-52442.