CVE-2023-38501

The application contains a reflected cross-site scripting via URL-parameter ?k304=... and ?setck=...

Details

A reflected cross-site scripting (XSS) vulnerability exists in the web interface of the application that could allow an attacker to execute malicious javascript code by tricking users into accessing a malicious link.

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 your copyparty accounts, unless you have inspected your logs and found no trace of attacks.

Checking for exposure

if copyparty is running behind a reverse proxy, you can check the access-logs for traces of attacks, by grepping for URLs containing ?hc= with < somewhere in its value, for example using the following command:

• nginx:

  (gzip -dc access.log*.gz; cat access.log) | sed -r 's/" [0-9]+ .*//' | grep -iE '%0[da]%0[da]%0[da]%0[da]|[?&](hc|pw)=.*[<>]'
  

the above commands also check for attacks against GHSA-cw7j-v52w-fp5r

PoC

https://localhost:3923/?k304=y%0D%0A%0D%0A%3Cimg+src%3Dcopyparty+onerror%3Dalert(1)%3E

Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.

CVE-2023-38501 has a CVSS score of 6.3 (Medium). The vector is network-reachable, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.8.7); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2023-38501? CVE-2023-38501 is a medium-severity cross-site scripting (XSS) vulnerability in copyparty (pip), affecting versions <= 1.8.6. It is fixed in 1.8.7. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
2. How severe is CVE-2023-38501? CVE-2023-38501 has a CVSS score of 6.3 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of copyparty are affected by CVE-2023-38501? copyparty (pip) versions <= 1.8.6 is affected.
4. Is there a fix for CVE-2023-38501? Yes. CVE-2023-38501 is fixed in 1.8.7. Upgrade to this version or later.
5. Is CVE-2023-38501 exploitable, and should I be worried? Whether CVE-2023-38501 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2023-38501 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2023-38501? Upgrade copyparty to 1.8.7 or later.