CVE-2026-6909
Reflected Cross-Site Scripting in ATutor
Publication date: 2026-05-11
Last updated on: 2026-05-11
Assigner: CERT.PL
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| atutor | atutor | From 2.2.4 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-79 | The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability is a Reflected Cross-Site Scripting (XSS) issue found in the /install/upgrade.php endpoint of ATutor. An attacker can craft a special URL that, when visited by a victim, causes arbitrary JavaScript code to execute in the victim's browser.
How can this vulnerability impact me? :
The impact of this vulnerability is that an attacker can execute arbitrary JavaScript in the context of the victim's browser. This can lead to theft of sensitive information, session hijacking, or performing actions on behalf of the victim without their consent.
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability can be detected by identifying attempts to access the /install/upgrade.php endpoint with suspicious or specially crafted URLs that include JavaScript code or unusual query parameters.
A practical approach is to monitor web server logs for requests to /install/upgrade.php containing suspicious input patterns that might trigger reflected XSS.
Example commands to detect such attempts include using grep on web server logs to find requests to the vulnerable endpoint:
- grep "/install/upgrade.php" /var/log/apache2/access.log
- grep -i "<script>" /var/log/apache2/access.log
- grep -E "(\%3Cscript\%3E|<script>)" /var/log/apache2/access.log
Additionally, using web vulnerability scanners that test for reflected XSS on the /install/upgrade.php endpoint can help detect this vulnerability.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation steps include restricting or disabling access to the /install/upgrade.php endpoint, especially if the installation or upgrade process is no longer needed.
Since the product is no longer actively supported and only version 2.2.4 is confirmed vulnerable, consider removing or isolating the vulnerable ATutor installation from public access.
Implement web application firewall (WAF) rules to block requests containing suspicious input patterns targeting the /install/upgrade.php endpoint.
Educate users to avoid clicking on suspicious links that could exploit this reflected XSS vulnerability.