CVE-2026-31717

HIGH EPSS 35.0%
Published May 1, 20261mo ago · Modified Jun 17, 20261w ago
8.8 CVSS 3.1
High
Find Similar
Published May 1, 2026 1mo ago
Last Modified Jun 17, 2026 1w ago

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate owner of durable handle on reconnect Currently, ksmbd does not verify if the user attempting to reconnect to a durable handle is the same user who originally opened the file. This allows any authenticated user to hijack an orphaned durable handle by predicting or brute-forcing the persistent ID. According to MS-SMB2, the server MUST verify that the SecurityContext of the reconnect request matches the SecurityContext associated with the existing open. Add a durable_owner structure to ksmbd_file to store the original opener's UID, GID, and account name. and catpure the owner information when a file handle becomes orphaned. and implementing ksmbd_vfs_compare_durable_owner() to validate the identity of the requester during SMB2_CREATE (DHnC).

CVSS Details

Base Score
8.8
Exploitability
2.8
Impact
5.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
35.0% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Affected Products 4

VendorProductVersionRange
linuxlinux_kernel*≥6.6.32  –  <6.7
linuxlinux_kernel*≥6.9  –  <6.18.25
linuxlinux_kernel*≥6.19  –  <7.0.2
linuxlinux_kernel7.1any

References 5

  • git.kernel.org https://git.kernel.org/stable/c/00ce8d6789dae72d042a4522264964c72891ca37
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/49110a8ce654bbe56bef7c5e44cce31f4b102b8a
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/712cdf917e77a6444ce3836874829d770db20ee6
  • git.kernel.org https://git.kernel.org/stable/c/c7f0f0d01c88bdcb8b1694d7d321670013f7ed7d
  • git.kernel.org https://git.kernel.org/stable/c/c908c853f304a4969b5aa10eba0b50350cc65b80
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/00ce8d6789dae72d042a4522264964c72891ca37
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/49110a8ce654bbe56bef7c5e44cce31f4b102b8a
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c908c853f304a4969b5aa10eba0b50350cc65b80
    Patch