CVE-2025-54589 is a medium-severity (CVSS 6.3) Cross-site Scripting (XSS) vulnerability in copyparty. 1 public exploit reference exists, so weaponization risk is real. A fix is available for copyparty — see the affected versions and patch details below.
copyparty Reflected XSS via Filter Parameter
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-54589.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2025-54589 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
copypartyReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
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):
https://127.0.0.1:3923/?ru&filter=</script><script>alert(1)</script>
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | copyparty | all versions | 1.18.7pip install --upgrade 'copyparty==1.18.7' |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Copyparty 1.18.6 - Reflected Cross-Site Scripting (XSS)
by Byte Reaper · Aug 3, 2025
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for copyparty, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update copyparty to 1.18.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-54589 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-54589 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-54589. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
How to detect CVE-2025-54589
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2025-54589 -u https://target- Template
- Copyparty <=1.18.6 - Cross-Site Scripting
- Severity
- medium
- Impact
- Attackers can execute arbitrary JavaScript in victim browsers through malicious URLs containing XSS payloads in the filter parameter, potentially leading to session hijacking.
- Remediation
- Upgrade Copyparty to version 1.18.7 or later to mitigate this vulnerability.
Template by ProjectDiscovery nuclei-templates (s-cu-bot), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2025-54589 in your dependencies?
O3 Security finds CVE-2025-54589 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.