CVE-2025-27145: low-severity vulnerability in 9001 copyparty
copyparty renders unsanitized filenames as HTML when user uploads empty files
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 3.6epss 0.5%
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.
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
Affected products
9001 · copypartyRelated CVEs — 9001 copyparty
In the same product, most dangerous first.
CVE-2023-37474HIGHPath traversal in copypartyEPSS 44.9%CVE-2023-38501MEDIUMcopyparty vulnerable to reflected cross-site scripting via k304 parameterEPSS 9.2%CVE-2025-54589MEDIUMcopyparty Reflected XSS via Filter ParameterEPSS 2.4%CVE-2025-54796HIGHCopyparty is vulnerable to Regex Denial of Service (ReDoS) attacks through "Recent Uploads" pageEPSS 0.5%CVE-2025-54423MEDIUMcopyparty has a DOM-Based XSS vulnerability when displaying multimedia metadataEPSS 0.5%CVE-2026-30974MEDIUMCopyparty volflag `nohtml` did not block javascript in svg filesEPSS 0.4%