CVE-2026-31433: Linux kernel · ksmbd: fix potencial OOB in get_file_all_info() for compound requests
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.8 High.
Data as of 12 Nov 2026, 00:34 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 8.8 |
|---|
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 22 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 11 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Linux Linux | Affected
| Fixed in– |
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.
References
- git.kernel.org/stable/c/3a852f9d1c981fb14f6bf4e24999e0ea8088a7d7 (opens in a new tab)
- git.kernel.org/stable/c/4cca3eff2099b18672934a39cee70aed835d652c (opens in a new tab)
- git.kernel.org/stable/c/358cdaa1f7fbf2712cb4c5f6b59cb9a5c673c5fe (opens in a new tab)
- git.kernel.org/stable/c/7aec5a769d2356cbf344d85bcfd36de592ac96a5 (opens in a new tab)
- git.kernel.org/stable/c/b0cd9725fe2bcc9f37d096b132318a9060373f5d (opens in a new tab)
- git.kernel.org/stable/c/9d7032851d6f5adbe2739601ca456c0ad3b422f0 (opens in a new tab)
- git.kernel.org/stable/c/beef2634f81f1c086208191f7228bce1d366493d (opens in a new tab)