** DISPUTED ** fs/nfsd/nfs3xdr.c in the Linux kernel through 5.10.8, when there is an NFS export of a subdirectory of a filesystem, allows remote attackers to traverse to other parts of the filesystem via READDIRPLUS. NOTE: some parties argue that such a subdirectory export is not intended to prevent this attack; see also the exports(5) no_subtree_check default behavior. CREATE(Triage):(User=admin) [CVE-2021-3178|https://nvd.nist.gov/vuln/detail/CVE-2021-3178]