GHSA-cw7j-v52w-fp5r copyparty vulnerable to reflected cross-site scripting via hc parameter
Reflected XSS in copyparty allows attackers to execute scripts via malicious links, potentially modifying or deleting files.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is GHSA-cw7j-v52w-fp5r?
GHSA-cw7j-v52w-fp5r is a cross-site scripting vulnerability in copyparty, published on 21 Jul 2023. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Summary
The application contains a reflected cross-site scripting via URL-parameter ?hc=...
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 -E '[?&](hc|pw)=.*[<>]'
PoC
http://127.0.0.1:3923/?hc="><script>alert(1);</script>http://127.0.0.1:3923/?pw=<script>alert(1);</script>
Which versions are affected by GHSA-cw7j-v52w-fp5r?
2 open source packages ship an affected version, including copyparty.
| Package | Affected | Fixed in |
|---|---|---|
copyparty PyPI | All versions | 1.8.6 |
copyparty PyPI | All versions | 1.8.6 |
How do I fix GHSA-cw7j-v52w-fp5r?
Upgrade copyparty to 1.8.6 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is GHSA-cw7j-v52w-fp5r being exploited?
There is no known exploitation of GHSA-cw7j-v52w-fp5r in the wild and no public exploit code.