CVE-2025-39943

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

ksmbd: smbdirect: validate data_offset and data_length field of smb_direct_data_transfer

If data_offset and data_length of smb_direct_data_transfer struct are invalid, out of bounds issue could happen. This patch validate data_offset and data_length field in recv_done.

This vulnerability presents no risk to Red Hat Enterprise Linux environments because the in-kernel SMB server (ksmbd) is not enabled or provided in supported kernel builds. The underlying issue stems from improper boundary checking of SMB Direct data transfer packets, which could potentially trigger an out-of-bounds memory condition on systems running the upstream kernel server. Because Red Hat utilizes user-space Samba services rather than kernel-based SMB implementations, supported Red Hat platforms are not impacted.