CyberRota Analysis
AI-GeneratedThe vulnerability in the Linux kernel allows clients to overwrite data on a destination file in a read-only share or with insufficient permissions, due to missing permission checks in the FSCTL_DUPLICATE_EXTENTS_TO_FILE functionality. This could lead to unauthorized data modification, posing a significant risk to data integrity. Organizations using affected Linux systems, particularly those relying on SMB file sharing, should prioritize applying patches to mitigate this critical security flaw.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: add permission checks for FSCTL_DUPLICATE_EXTENTS_TO_FILE The FSCTL_DUPLICATE_EXTENTS_TO_FILE arm of smb2_ioctl() overwrites the destination file's data via vfs_clone_file_range() with neither the share-level KSMBD_TREE_CONN_FLAG_WRITABLE check nor a per-handle fp->daccess check that the other write-bearing arms carry. A client can overwrite destination data on a read-only share, or from a handle opened with only FILE_WRITE_ATTRIBUTES (which still yields an FMODE_WRITE filp). FILE_WRITE_ATTRIBUTES-only destination handle overwrote the file's data via the clone. Add both checks, matching the FSCTL_SET_SPARSE permission fix; require FILE_WRITE_DATA since this writes data.