cbcvebase.
CVE-2023-38501
published 2023-07-25

CVE-2023-38501: copyparty is file server software. Prior to version 1.8.7, the application contains a reflected cross-site scripting via URL-parameter `?k304=...` and…

PriorityP343medium6.1CVSS 3.1
AVNACLPRNUIRSCCLILAN
EXPLOIT
EPSS
6.19%
92.6th percentile
copyparty is file server software. Prior to version 1.8.7, the application contains a reflected cross-site scripting via URL-parameter `?k304=...` and `?setck=...`. The worst-case outcome of this is being able to move or delete existing files on the server, or upload new files, using the account of the person who clicks the malicious link. It is recommended to change the passwords of one's copyparty accounts, unless one have inspected one's logs and found no trace of attacks. Version 1.8.7 contains a patch for the issue.

Affected

3 ranges
VendorProductVersion rangeFixed in
9001copyparty< 1.8.71.8.7
9001copyparty>= 0 < 007d948cb982daa05bc6619cd20ee55b7e834c38007d948cb982daa05bc6619cd20ee55b7e834c38
9001copyparty>= 0 < 1.8.71.8.7

Detection & IOCsextracted from sources · hover to see the quote

url{{BaseURL}}/?k304=y%0D%0A%0D%0A%3Cimg+src%3Dcopyparty+onerror%3Dalert(1)%3E
url{{BaseURL}}/?k304=y%0D%0A%0D%0A%3Cimg+src%3Dcopyparty+onerror%3Dalert(document.domain)%3E
other?k304=
other?setck=
  • Detect exploitation attempts by matching HTTP requests containing CRLF injection (%0D%0A) in the k304 or setck URL parameters, combined with HTML tag injection patterns.
  • Use Nuclei matcher logic: HTTP 200 response, content-type text/html, and body containing both the injected img tag and the string '">go to' to confirm reflected XSS execution.
  • Identify exposed copyparty instances via Shodan (title:"copyparty"), FOFA (title="copyparty"), or Google (intitle:"copyparty") for attack surface enumeration.
  • Flag copyparty versions <= 1.8.6 as vulnerable; patch is present in version 1.8.7.
  • ·The XSS is reflected (not stored), requiring user interaction — a victim must click a crafted malicious link for exploitation to succeed.
  • ·Impact includes file manipulation (move, delete, upload) using the victim's authenticated session, not just cookie theft — scope of post-exploitation is broader than typical XSS.
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