A critical security vulnerability, identified as CVE-2025-65516, has been discovered and patched in Seafile Community Edition. This article provides a detailed overview of the vulnerability, its technical details, potential impact, and the necessary steps to mitigate the risk.
Overview
CVE-2025-65516 is a stored cross-site scripting (XSS) vulnerability affecting Seafile Community Edition versions prior to 13.0.12. The vulnerability allows an attacker to inject malicious JavaScript code into the Seafile server, which can then be executed in the browsers of other users who access the affected data. This could lead to session hijacking, data theft, or other malicious activities.
Technical Details
The vulnerability stems from insufficient input validation when handling SVG files uploaded to Seafile. When Seafile is configured to use the Golang file server, a malicious user can upload a specially crafted SVG file containing embedded JavaScript code. By then sharing this SVG file using a public link, the attacker can trick other users into clicking the link and triggering the execution of the malicious script within their browser context. The browser interprets the SVG, including the malicious JavaScript, leading to the XSS execution.
CVSS Analysis
Due to the contextual nature of the environment and specific details, a CVSS score is not available at this time. However, given the potential for user impersonation, data theft, and other malicious activities, this vulnerability should be considered of medium to high severity depending on the specific organizational context.
Possible Impact
Successful exploitation of this vulnerability could have significant consequences, including:
- Account Takeover: An attacker could potentially steal user session cookies and gain unauthorized access to user accounts.
- Data Theft: Sensitive data stored within Seafile could be accessed and exfiltrated by the attacker.
- Malware Distribution: The attacker could use the compromised Seafile server to distribute malware to other users.
- Defacement: The attacker could modify the appearance of the Seafile web interface to mislead or deface the site.
Mitigation and Patch Steps
The recommended mitigation is to upgrade Seafile Community Edition to version 13.0.12 or later. This version includes a fix that properly sanitizes SVG files to prevent the execution of malicious JavaScript code. To upgrade, follow the official Seafile upgrade instructions. The following is a summary of recommended steps:
- Backup your Seafile data: Ensure you have a complete backup of your Seafile data directory before proceeding.
- Stop the Seafile server: Use the appropriate commands to stop the Seafile server processes.
- Upgrade Seafile: Follow the instructions in the Seafile upgrade manual for your specific operating system and setup.
- Start the Seafile server: After the upgrade is complete, start the Seafile server processes.
- Verify the upgrade: Confirm that the Seafile server is running version 13.0.12 or later.
