# CVE-2023-3866: linux: In the Linux kernel, the following vulnerability has been resolved:  ksmbd: validate session id and tree id in the co...

CVE-2023-3866 is fixed in linux on 1 platform, first by DEBIAN-CVE-2023-3866, released August 16, 2025. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2023-3866
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.1265
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 16, 2025

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 6.1.37-1 | [DEBIAN-CVE-2023-3866](https://patchblox.com/security/data/fix/linux/debian-cve-2023-3866.md) | Aug 16, 2025 |
| Linux | linux Debian 13.5 (trixie) | 6.3.11-1 | [DEBIAN-CVE-2023-3866](https://patchblox.com/security/data/fix/linux/debian-cve-2023-3866.md) | Aug 16, 2025 |
| Linux | linux Debian 14 | 6.3.11-1 | [DEBIAN-CVE-2023-3866](https://patchblox.com/security/data/fix/linux/debian-cve-2023-3866.md) | Aug 16, 2025 |

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