CVE-2026-68083
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data tampering, service disruption.
- Exploit odds
- 0.5% chance of exploitation in the next 30 days (EPSS).
- Fix
- No patch or advisory is linked yet. Look at mitigations or restrict exposure.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Details
- Published
- Last modified
- Exploit probability
- 0.5% · EPSS, next 30 days
- Record status
- Received
Attack profile CVSS 3.1 · 9.1
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
References
- https://git.kernel.org/stable/c/1c8951963d8ed357f70f59e0ad4ddce2199d2016
- https://git.kernel.org/stable/c/489d1ded01425c0fb33418172c0e4e588467526b
- https://git.kernel.org/stable/c/98185b3025beeae92d1fe700d5db26b9ac4bf025
- https://git.kernel.org/stable/c/a2516be69048856e2a49a51e00975dc59431f95c
- https://git.kernel.org/stable/c/c7c884a1305aa4540eb7942a50bd356b34120e1f
- https://git.kernel.org/stable/c/f1f53dc95edfb3d2072e5e8cd8eb9a2fe7d7f2d0