CVE-2026-31717

Updated on 01 May 2026

Severity

8.8 High severity

Details

CVSS score
8.8

Overview

About vulnerability

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). A flaw was found in ksmbd, a component of the Linux kernel. This vulnerability allows an authenticated user to hijack an orphaned durable handle by predicting or brute-forcing its persistent ID. This could lead to unauthorized access to file sessions and potentially sensitive data or services.

Details

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
Debian 13 Planned