CVE-2026-93353

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.

CVSS v3 3.1 LOW

3.1^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.6 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://euriconicacio.github.io/blog/cve-2026-93353-a-volume-guard-enforced-one-call-site-at-a-time/
https://www.vulncheck.com/advisories/copyparty-sftp-volume-restriction-bypass-via-mkdir-rmdir-chattr-handlers

Configurations

No configuration.

History

30 Sep 2026, 21:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~5.3~~	v2 : unknown v3 : 3.1

24 Sep 2026, 21:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-24 21:18

Updated : 2026-09-30 21:17

NVD link : CVE-2026-93353

Mitre link : CVE-2026-93353

CVE.ORG link : CVE-2026-93353

JSON object : View

Products Affected

No product.

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

CWE-424

Improper Protection of Alternate Path

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