---
id: CVE-2026-99113
title: 'ksmbd: zero the FS_OBJECT_ID_INFORMATION buffer before filling it in'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ksmbd: zero the FS_OBJECT_ID_INFORMATION buffer before filling it in

  smb2_get_info_filesystem() reports 64 bytes for FS_OBJECT_ID_INFORMATION,
  that is the whole of str…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <
    dbd0f13de153d7094b85034daffa7533d7c2b17a
  - >-
    Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <
    90898571fb2c6813c007a62833dd65c00481d44e
  - >-
    Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <
    1a35a81c302b36fe4acd35b47b51d5d73e89ba0a
  - >-
    Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <
    3fc33ac2125b60f103592b83821f69f3f9aa23ba
  - >-
    Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <
    898cb4f2e12a5ddea1b2d821cc642c3100f46da7
  - >-
    Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <
    015fffa48e96ca8d73a627445341ccff86b02251
  - >-
    Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <
    399aa12450a61a5c73dc77e73f069ece9687c95d
  - Linux 5.15
published: '2026-10-28'
updated: '2026-10-30'
sourceUpdated: '2026-10-30T12:41:51.384Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-99113'
references:
  - url: 'https://git.kernel.org/stable/c/dbd0f13de153d7094b85034daffa7533d7c2b17a'
  - url: 'https://git.kernel.org/stable/c/90898571fb2c6813c007a62833dd65c00481d44e'
  - url: 'https://git.kernel.org/stable/c/1a35a81c302b36fe4acd35b47b51d5d73e89ba0a'
  - url: 'https://git.kernel.org/stable/c/3fc33ac2125b60f103592b83821f69f3f9aa23ba'
  - url: 'https://git.kernel.org/stable/c/898cb4f2e12a5ddea1b2d821cc642c3100f46da7'
  - url: 'https://git.kernel.org/stable/c/015fffa48e96ca8d73a627445341ccff86b02251'
  - url: 'https://git.kernel.org/stable/c/399aa12450a61a5c73dc77e73f069ece9687c95d'
tags:
  - cve.org
epss: 0.00173
epssPercentile: 0.06789
ingestedAt: '2026-10-28T11:09:40.451Z'
---

## Overview

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

ksmbd: zero the FS_OBJECT_ID_INFORMATION buffer before filling it in

smb2_get_info_filesystem() reports 64 bytes for FS_OBJECT_ID_INFORMATION,
that is the whole of struct object_id_info, but writes only 46 of them:

 - objid[] is 16 bytes, and when the volume UUID is not available only
   sizeof(stfs.f_fsid) (8) bytes are copied into it;
 - extended_info.version_string[] is STRING_LENGTH (28) bytes, and only
   strlen("1.1.0") (5) bytes are copied into it.

The response buffer is zeroed on allocation (kvzalloc() in
smb2_allocate_rsp_buf()), so for a standalone request the remaining 31
bytes are zero.  In a compound request they need not be.  The offset of
the next response is advanced by the length pinned for the previous one,
so if a preceding command wrote its reply into the buffer and then
failed, smb2_set_err_rsp() pins only the short error response and the
next reply lands inside the area that has already been written.  Only
the header is cleared there:

	memset((char *)rsp_hdr, 0, sizeof(struct smb2_hdr) + 2);

The client then receives up to 31 bytes of a response it was not meant
to see, including one that failed with an access denied error.

Clear the structure before filling it in.  As a side effect
version_string is now NUL terminated.

## Affected

- `Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < dbd0f13de153d7094b85034daffa7533d7c2b17a`
- `Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 90898571fb2c6813c007a62833dd65c00481d44e`
- `Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 1a35a81c302b36fe4acd35b47b51d5d73e89ba0a`
- `Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 3fc33ac2125b60f103592b83821f69f3f9aa23ba`
- `Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 898cb4f2e12a5ddea1b2d821cc642c3100f46da7`
- `Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 015fffa48e96ca8d73a627445341ccff86b02251`
- `Linux >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 399aa12450a61a5c73dc77e73f069ece9687c95d`
- `Linux 5.15`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.