# CVE-2026-104102: copyparty FTP path traversal in upload

Source: https://junglewise.ai/threats/cve-2026-104102-copyparty-ftp-upload-outside-defined-volumes-limited-path  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-12. Updated: 2026-10-15  
License: CC BY 4.0 with a link back

CVE-2026-104102 · Severity: medium · CVSS 4 · Published 2026-10-12

copyparty is a file sharing application with optional FTP/FTPS servers. When the FTP server is enabled (it is disabled by default), authenticated attackers can upload files to any directory that the copyparty process has write access to, potentially compromising other software on the same system if it automatically executes uploaded files. The vulnerability is limited to new file creation with randomized suffixes and does not allow reading existing files.

Technologies: [copyparty (PyPI)](https://junglewise.ai/threats/technologies/copyparty). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-104102 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-104102 being exploited in the wild.

**How severe is CVE-2026-104102?** Medium severity, with a CVSS score of 4, published 12 October 2026.

**Which products and versions are affected?** 9001 Copyparty < 1.20.19; copyparty (PyPI) < 1.20.19, ECOSYSTEM:introduced=0,fixed=1.20.19.

**Is there a fix for CVE-2026-104102?** Yes. copyparty (PyPI): upgrade to 1.20.19 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-104102 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-104102?** Check whether you run 9001 Copyparty or copyparty (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- copyparty (PyPI): upgrade to 1.20.19 or later

  ```sh
  pip install "copyparty>=1.20.19"
  ```


## Technical details

This is a limited path traversal vulnerability in copyparty's FTP/FTPS upload handler that allows authenticated users to write files outside the configured volumes. The attack requires the FTP server to be explicitly enabled, an attacker to authenticate with valid credentials, and a precondition that other software on the system automatically executes newly created files. The vulnerability does not permit file overwrite, download of existing files, or arbitrary code execution through copyparty itself.

## Affected products

- 9001 copyparty < 1.20.19

## Identifiers

- CVE-2026-104102
- GHSA-phv8-wgjp-g4p9

## Timeline

- 2026-07-27: disclosed
- 2026-10-15: advisory

## References

- [https://github.com/9001/copyparty/security/advisories/GHSA-phv8-wgjp-g4p9](https://github.com/9001/copyparty/security/advisories/GHSA-phv8-wgjp-g4p9)

## Related threats

- [Copyparty file/dirkey confusion authorization bypass](https://junglewise.ai/threats/cve-2026-70657-copyparty-file-dirkey-confusion-authorization-bypass)
- [PYSEC-2026-1279 - copyparty: Sharing a single file does not fully restrict access to other files in source folder](https://junglewise.ai/threats/cve-2025-58753-copyparty-sharing-a-single-file-does-not-fully-restrict-access-to)
- [PYSEC-2026-1275 - copyparty allows Regex Denial of Service (ReDoS) in the upload listing](https://junglewise.ai/threats/cve-2025-54796-copyparty-allows-regex-denial-of-service-redos-in-the-upload)
- [PYSEC-2026-1276 - copyparty Reflected XSS via Filter Parameter](https://junglewise.ai/threats/cve-2025-54589-copyparty-reflected-xss-via-filter-parameter)
- [PYSEC-2026-1277 - copyparty has DOM-Based XSS vulnerability when displaying multimedia metadata](https://junglewise.ai/threats/cve-2025-54423-copyparty-has-dom-based-xss-vulnerability-when-displaying)