Summary
XSS via .py file containing script tag interpreted as HTML
A vulnerability exists in the file preview/browsing feature of the application, where files with a .py extension that contain JavaScript code wrapped in <script> tags may be interpreted and executed as HTML in certain modes. This leads to a stored XSS vulnerability.
Affected Versions
- <= 4.0.0-rc.3
PoC
Create a .py file with arbitrary JavaScript content wrapped in <script> tags. For example:
<script>alert(document.cookie);</script>
When a victim views the file in browsing mode (e.g., a rendered preview), the JavaScript is executed in the browser context.
Attack vector
An attacker can place such a .py file in the system via remote channels, such as:
- Convincing a webmaster to download or upload the file;
- Tricking users into accessing a file link via public URLs.
Required permissions
- None, if public or visitor access is enabled.
- If the file is uploaded by a user with elevated permissions, potential privilege boundaries may be crossed.
User interaction
Yes. The user must manually click to switch to the browsing or preview mode to trigger the script. And seems only when using ISO-8859-1 encoding.
Scope
- Unchanged
(S:U)- The attack does not cross system or privilege boundaries in general. - ⚠️ Controversial edge case: If sensitive preview files are accessible due to misconfiguration, scope could be considered Changed
(S:C).
Recommendations
- Treat all previewed file types (including non-HTML like .py) as plain text unless explicitly sanitized.
- Disable rendering modes that can interpret user-uploaded content as HTML.
Timeline
| Date | Event |
|---|---|
| 2025-06-17 | Vulnerability reported |
| 2025-06-17 | Comminuty Manager confirmed |
| 2025-06-17 | Fixed |
Credits
- Discovered by: @zyk2507
- Reported to: The OpenList Team
- Analyzed and confirmed by: @jyxjjj
- Fixed by: @cxw620
- Fixed in:
4.0.0-rc.4
Impact
- Confidentiality: User information including cookies, login state, and localStorage may be accessed. Some files that only can be viewed via this user will leak too.
- Integrity & Availability: Not directly impacted.
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-2025-50183 has a CVSS score of 6.5 (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 (4.0.0-rc.4); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
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. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2025-50183? CVE-2025-50183 is a medium-severity cross-site scripting (XSS) vulnerability in @openlist-frontend/openlist-frontend (npm), affecting versions <= 4.0.0-rc.3. It is fixed in 4.0.0-rc.4. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
- How severe is CVE-2025-50183? CVE-2025-50183 has a CVSS score of 6.5 (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.
- Which versions of @openlist-frontend/openlist-frontend are affected by CVE-2025-50183? @openlist-frontend/openlist-frontend (npm) versions <= 4.0.0-rc.3 is affected.
- Is there a fix for CVE-2025-50183? Yes. CVE-2025-50183 is fixed in 4.0.0-rc.4. Upgrade to this version or later.
- Is CVE-2025-50183 exploitable, and should I be worried? Whether CVE-2025-50183 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
- What actually determines whether CVE-2025-50183 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.
- How do I fix CVE-2025-50183? Upgrade
@openlist-frontend/openlist-frontendto 4.0.0-rc.4 or later.