copyparty is a portable file server. Prior to 1.20.19, FTP upload path handling does not confine destinations to configured copyparty volumes. When FTP or FTPS is explicitly enabled, a low-privileged authenticated user can submit traversal paths during upload to create a new file outside configured volumes wherever the copyparty process has write permission.
The attacker cannot read or overwrite files, the output name receives a randomized suffix, and copyparty does not execute the file; however, unrelated software on the same host could process the newly created file. This issue is fixed in version 1.20.19.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
Low
Partial data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products
9001:copyparty
References 3
https://github.com/9001/copyparty/commit/b331bb1c8c8cc306b91e4d94221969335a7a3e…
security-advisories@github.com
https://github.com/9001/copyparty/releases/tag/v1.20.19
security-advisories@github.com
https://github.com/9001/copyparty/security/advisories/GHSA-phv8-wgjp-g4p9
security-advisories@github.com