CVE-2023-3866: linux kernel Null Dereference — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate session id and tree id in the compound request This patch validate session id and tree id in compound request. If first operation in the compound is SMB2 ECHO request, ksmbd bypass session and tree validation. So work->sess and work->tcon could be NULL. If secound request in the compound access work->sess or tcon, It cause NULL pointer dereferecing error.

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-476 CWE-476

Affected Products

Vendor	Product	Versions
linux	linux_kernel	5.15 — 5.15.121
linux	linux_kernel	5.16 — 6.1.36
linux	linux_kernel	6.2 — 6.3.10
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/5005bcb4219156f1bf7587b185080ec1da08518e https://git.kernel.org/stable/c/854156d12caa9d36de1cf5f084591c7686cc8a9d https://git.kernel.org/stable/c/d1066c1b3663401cd23c0d6e60cdae750ce00c0f https://git.kernel.org/stable/c/eb947403518ea3d93f6d89264bb1f5416bb0c7d0

Frequently Asked Questions

What is CVE-2023-3866? +

In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate session id and tree id in the compound request This patch validate session id and tree id in compound request. If first operation in the compound is SMB2 ECHO request, ksmbd bypass session and tree validation. So work->sess and work->tcon could be NULL. If secound request in the compound access work->sess or tcon, It cause NULL pointer dereferecing error. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2023-3866? +

CVE-2023-3866 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-3866? +

CVE-2023-3866 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-3866? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2023-3866