copyparty Reflected XSS via Filter Parameter

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L

EPSS

• CVE-2025-54589: 2.38% estimated exploitation activity in the next 30 days; percentile 83.88 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Unauthorized reflected Cross-Site-Scripting when accessing the URL for recent uploads with the filter parameter containing JavaScript code. Details When accessing the recent uploads page at /?ru, users can filter the results using an input field at the top. This field appends a filter parameter to the URL, which reflects its value directly into a <script block without proper escaping. This vulnerability allows for reflected Cross-Site Scripting (XSS) and can be exploited against both authenticated and unauthenticated users, enabling unwanted actions in the victims browser. PoC A URL like this will execute alert(1):

Published by the source

31 Jul 2025, 13:48 UTC

Last modified by the source

7 Jul 2026, 17:56 UTC

Source last checked

26 Oct 2026, 13:32 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-8mx2-rjh8-q3jq

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-8mx2-rjh8-q3jq

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# Patch Next advisory brief: CVE-2025-54589

Advisory: copyparty Reflected XSS via Filter Parameter
IDs: CVE-2025-54589, GHSA-8mx2-rjh8-q3jq
Record: https://patchnext.com/advisories/cve-2025-54589 (revision 2, source checked 26 Oct 2026, 13:32 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: copyparty 1.18.7. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI copyparty: affected <= 1.18.6; fixed in 1.18.7

## Suggested inspection (read-only)
- `python -m pip show copyparty`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on copyparty.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-8mx2-rjh8-q3jq (OSV record GHSA-8mx2-rjh8-q3jq lists affected ranges: PyPI copyparty >=0 <1.18.7 (fixed))
- Verified: https://github.com/advisories/GHSA-8mx2-rjh8-q3jq (GitHub-reviewed advisory GHSA-8mx2-rjh8-q3jq lists affected ranges: PyPI copyparty >=0 <=1.18.6)

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