Overview
CVE-2025-56526 is a cross-site scripting (XSS) vulnerability found in Kotaemon version 0.11.0. This vulnerability allows attackers to execute arbitrary JavaScript code within the context of a user’s browser by injecting malicious code through a specially crafted PDF file. Successful exploitation of this vulnerability could lead to session hijacking, data theft, and other malicious activities.
Technical Details
The vulnerability stems from insufficient sanitization of data extracted from PDF files processed by Kotaemon. Specifically, the application fails to properly sanitize input when rendering PDF content, allowing an attacker to embed malicious JavaScript code within a PDF document. When a user opens or previews this malicious PDF using Kotaemon, the embedded script executes, potentially compromising the user’s account or system.
The vulnerability has been identified and addressed in a subsequent commit on the Kotaemon GitHub repository. Details about the fixing commit can be found in the references section.
CVSS Analysis
- Severity: MEDIUM
- CVSS Score: 6.1
A CVSS score of 6.1 indicates a medium severity vulnerability. While not critical, the potential impact of XSS vulnerabilities can be significant, especially if attackers target administrator accounts or sensitive user data. The attack complexity is relatively low, and exploitation is possible with a moderate level of effort.
Possible Impact
Exploitation of CVE-2025-56526 can have several serious consequences:
- Session Hijacking: Attackers can steal user session cookies, allowing them to impersonate legitimate users.
- Data Theft: Malicious scripts can access and steal sensitive data, including personal information, financial data, and confidential documents.
- Malware Distribution: Attackers can use the XSS vulnerability to inject malicious code that redirects users to phishing sites or downloads malware onto their systems.
- Defacement: The application interface can be defaced, causing damage to the brand reputation and potentially leading to a loss of user trust.
Mitigation and Patch Steps
To mitigate the risk posed by CVE-2025-56526, it is strongly recommended to take the following steps:
- Upgrade to a patched version: The most effective solution is to upgrade Kotaemon to a version that includes the fix for this vulnerability. Check the Kotaemon GitHub repository for the latest release and update instructions.
- Input Validation and Sanitization: If upgrading is not immediately possible, implement robust input validation and sanitization mechanisms to prevent the execution of malicious JavaScript code. Ensure that all data extracted from PDF files is properly escaped before being rendered in the user interface.
- Web Application Firewall (WAF): Employ a web application firewall (WAF) to detect and block XSS attacks. Configure the WAF to filter out potentially malicious code and block suspicious requests.
