CVE-2026-68431

A flaw was found in ksmbd in the Linux kernel. When handling Server Message Block version 2 (SMB2) transform requests, the system fails to validate the minimum Protocol Data Unit (PDU) size. An unauthenticated remote attacker can send a specially crafted, short transform packet, bypassing security checks. This leads to the system reading beyond allocated memory and potentially disclosing sensitive information to the attacker.

This issue affects systems running ksmbd (in-kernel SMB server). Short SMB2 transform packets on dialects without transform support bypass minimum PDU validation and reach header parsing with undersized buffers. Exploitation requires network access to a ksmbd service.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.