XSS in 9001 Copyparty
CVE-2025-27145
copyparty, a portable file server, has a DOM-based cross-site scripting vulnerability in versions prior to 1.16.15. The vulnerability is considered low-risk. By handing someone a maliciously-named file, and then tricking them into dragging the file into copyparty's Web-UI, an attacker could execute arbitrary javascript with the same privileges as that user. For example, this could give unintended read-access to files owned by that user. The bug is triggered by the drag-drop action itself; it is not necessary to actually initiate the upload. The file must be empty (zero bytes). Note that, as a general-purpose webserver, it is intentionally possible to upload HTML-files with arbitrary javascript in `<script>` tags, which will execute when the file is opened. The difference is that this vulnerability would trigger execution of javascript during the act of uploading, and not when the uploaded file was opened. Version 1.16.15 contains a fix.
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.005 (38.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 3.6 (Low). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N.
Affected products
- 9001 Copyparty — versions < 1.16.15
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Third Party Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2025-27145?
- CVE-2025-27145 is a low-severity vulnerability in 9001 Copyparty, classified under Cross-site Scripting. CVSS score: 3.6/10. Published 2025-02-25.
- How severe is CVE-2025-27145?
- Low severity. CVSS v3 base score is 3.6 out of 10.
- Is CVE-2025-27145 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.