CVE-2026-68083
CriticalCVSS 9.1Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
In the Linux kernel, the ksmbd (SMB) server has a vulnerability in path resolution in ksmbd_vfs_kern_path_create. An attacker can use '..' components to escape the shared resource, leading to privilege escalation or unauthorized access.
Risk Assessment
The risk includes the possibility of unauthorized access to files outside the shared resource, which can lead to confidentiality and integrity breaches.
Recommendation
It is recommended to apply the patch that roots the create walk at the share using LOOKUP_BENEATH and vfs_path_parent_lookup.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix path resolution in ksmbd_vfs_kern_path_create The SMB2 open lookup is rooted at the share with LOOKUP_BENEATH, but the create/mkdir/hardlink sink is not: ksmbd_vfs_kern_path_create() builds an absolute path with convert_to_unix_name() and resolves it from AT_FDCWD via start_creating_path(), so a ".." component is walked from the real filesystem root and escapes the export. An authenticated client races a missing path component so the rooted open lookup returns -ENOENT (taking the create branch) while the same component is present (a directory) when the create walk runs; the create then resolves ".." out of the share. Root the create walk at the share like the lookup and rename paths already are: resolve the parent with vfs_path_parent_lookup(..., LOOKUP_BENEATH, &share_conf->vfs_path) and create the final component with start_creating_noperm(). convert_to_unix_name() then has no callers and is removed.