CVE-2026-93353 copyparty SFTP Volume Restriction Bypass via mkdir/rmdir/chattr Handlers
Authenticated SFTP users can bypass volume restrictions to create, delete, or truncate files outside authorized directories via symlink traversal.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-93353?
CVE-2026-93353 is a low-severity path traversal vulnerability in 9001 copyparty, published on 24 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
copyparty contains a volume restriction bypass vulnerability in its SFTP front end that allows authenticated SFTP users to create, remove, and truncate arbitrary paths outside permitted volume boundaries by exploiting three handlers that bypass the xvol volflag enforcement. The _mkdir, _rmdir, and _chattr handlers construct destination paths using vfs.get(), vn.canonical(), and os.path.join() without invoking the chk_ap access check, enabling attackers to traverse symlinks leaving a volume's top directory and perform unauthorized file creation, deletion, or truncation via SSH_FXP_SETSTAT operations on paths outside any volume the account is authorized to access.
Which versions are affected by CVE-2026-93353?
How do I fix CVE-2026-93353?
No fix has been published for CVE-2026-93353 yet. Limit exposure of the affected software until one is available.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-93353 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-93353 exists.
Sources
Also known as GHSA-3465-46r4-pj75.