CVE-2026-31433

HIGH

ksmbd: fix potencial OOB in get_file_all_info() for compound requests

Title source: cna
STIX 2.1

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix potencial OOB in get_file_all_info() for compound requests When a compound request consists of QUERY_DIRECTORY + QUERY_INFO (FILE_ALL_INFORMATION) and the first command consumes nearly the entire max_trans_size, get_file_all_info() would blindly call smbConvertToUTF16() with PATH_MAX, causing out-of-bounds write beyond the response buffer. In get_file_all_info(), there was a missing validation check for the client-provided OutputBufferLength before copying the filename into FileName field of the smb2_file_all_info structure. If the filename length exceeds the available buffer space, it could lead to potential buffer overflows or memory corruption during smbConvertToUTF16 conversion. This calculating the actual free buffer size using smb2_calc_max_out_buf_len() and returning -EINVAL if the buffer is insufficient and updating smbConvertToUTF16 to use the actual filename length (clamped by PATH_MAX) to ensure a safe copy operation.

Scores

CVSS v3 8.8
EPSS 0.0004
EPSS Percentile 13.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Details

Status published
Products (18)
Linux/Linux < 6.6
Linux/Linux 5.15.145 - 5.15.203
Linux/Linux 5.15.203 - 5.15.*
Linux/Linux 6.1.168 - 6.1.*
Linux/Linux 6.1.71 - 6.1.168
Linux/Linux 6.12.80 - 6.12.*
Linux/Linux 6.18.21 - 6.18.*
Linux/Linux 6.19.11 - 6.19.*
Linux/Linux 6.6
Linux/Linux 6.6.131 - 6.6.*
... and 8 more
Published Apr 22, 2026
Tracked Since Apr 22, 2026