CVE-2025-59893: Sync Breeze & Disk Pulse CSRF Vulnerability

CVE-2025-59893 Overview

CVE-2025-59893 is a Cross-Site Request Forgery (CSRF) vulnerability affecting Sync Breeze Enterprise Server v10.4.18 and Disk Pulse Enterprise v10.4.18. This vulnerability allows an authenticated user to trick another user into performing unwanted actions within the application they are logged into. The root cause is the absence of proper CSRF token implementation in the affected web interfaces.

The vulnerability specifically impacts the command renaming functionality, where attackers can craft malicious requests to the /rename_command?sid= endpoint, manipulating the command_name parameter to execute unauthorized changes on behalf of authenticated victims.

Critical Impact

Attackers can hijack authenticated user sessions to perform unauthorized administrative actions, potentially leading to configuration tampering, data manipulation, and system compromise without victim awareness.

Affected Products

• Sync Breeze Enterprise Server v10.4.18
• Disk Pulse Enterprise v10.4.18
• Other Flexense products may be affected

Discovery Timeline

• 2026-01-28 - CVE-2025-59893 published to NVD
• 2026-01-29 - Last updated in NVD database

Technical Details for CVE-2025-59893

Vulnerability Analysis

This CSRF vulnerability exists due to the web interface's failure to implement anti-CSRF tokens when processing state-changing requests. When a user is authenticated to the Sync Breeze Enterprise Server or Disk Pulse Enterprise management interface, their browser maintains session cookies that automatically accompany all requests to the application.

An attacker can exploit this weakness by crafting a malicious webpage or email containing hidden forms or JavaScript that triggers requests to the vulnerable endpoints. When an authenticated administrator visits the attacker's page, their browser automatically includes their valid session credentials with the forged request, causing the application to process the malicious action as if it were legitimately initiated by the user.

The attack surface is network-accessible, meaning attackers do not need local access to the target system. However, user interaction is required—the victim must click a malicious link or visit a compromised page while authenticated to the vulnerable application.

Root Cause

The fundamental security flaw is the absence of CSRF protection mechanisms in the application's web interface. Modern web applications should implement anti-CSRF tokens—unique, unpredictable values that must accompany each state-changing request. These tokens are validated server-side to ensure requests originate from legitimate application pages rather than forged cross-origin requests.

The affected Flexense products fail to generate, embed, and validate such tokens, leaving all authenticated endpoints vulnerable to cross-site request forgery attacks. The /rename_command endpoint is specifically identified as exploitable, but other administrative functions may be similarly affected.

Attack Vector

The attack follows a classic CSRF exploitation pattern:

1. The attacker identifies authenticated endpoints that perform sensitive operations without CSRF token validation
2. The attacker crafts a malicious HTML page containing an auto-submitting form targeting the vulnerable endpoint (e.g., /rename_command?sid=)
3. The attacker delivers this page to the victim through social engineering (phishing email, malicious link, compromised website)
4. When the victim visits the attacker's page while authenticated to the Sync Breeze or Disk Pulse interface, their browser automatically submits the forged request with their valid session cookies
5. The application processes the request as legitimate, executing the attacker's desired action with the victim's privileges

The vulnerability specifically targets the command_name parameter via POST requests to /rename_command?sid=, enabling attackers to rename commands within the application. This could be leveraged for further attacks, including disguising malicious commands or disrupting normal operations.

Detection Methods for CVE-2025-59893

Indicators of Compromise

• Unexpected changes to command names or configurations in Sync Breeze or Disk Pulse Enterprise
• Server logs showing POST requests to /rename_command endpoints from unusual referrer URLs
• User reports of administrative changes they did not initiate
• Cross-origin requests to management interface endpoints in web server logs

Detection Strategies

• Review web server access logs for POST requests to /rename_command?sid= endpoints with external or missing Referer headers
• Implement web application firewall rules to detect and block requests with suspicious or absent origin headers
• Monitor audit logs for configuration changes and correlate with user activity to identify unauthorized modifications
• Deploy browser-based security solutions that alert on cross-origin form submissions to internal management interfaces

Monitoring Recommendations

• Enable detailed access logging on web management interfaces to capture full request details including Referer and Origin headers
• Configure alerts for administrative actions occurring outside normal business hours or from unexpected IP addresses
• Implement Security Information and Event Management (SIEM) rules to detect patterns consistent with CSRF exploitation
• Regularly audit system configurations to detect unauthorized changes that may indicate successful CSRF attacks

How to Mitigate CVE-2025-59893

Immediate Actions Required

• Restrict network access to Sync Breeze Enterprise and Disk Pulse Enterprise management interfaces to trusted IP addresses only
• Implement network segmentation to isolate management interfaces from general user networks
• Educate administrators about CSRF risks and advise against accessing untrusted links while authenticated to management interfaces
• Deploy a reverse proxy or web application firewall with CSRF protection capabilities in front of vulnerable applications

Patch Information

Consult the vendor advisory and INCIBE Security Notice for the latest patch information and updated versions that address this vulnerability. Organizations should prioritize updating to patched versions as they become available from Flexense.

Workarounds

• Implement network-level access controls using firewall rules to restrict management interface access to specific administrator workstations
• Configure the web server to validate Referer or Origin headers and reject requests with external or missing values
• Use separate browser profiles or isolated browser sessions when accessing administrative interfaces to prevent session cookie sharing
• Consider deploying a web application firewall with custom rules to inject CSRF tokens or block suspicious cross-origin requests

# Example firewall rule to restrict management interface access (iptables)
# Replace 192.168.1.0/24 with your trusted admin network
# Replace 8080 with your management interface port

iptables -A INPUT -p tcp --dport 8080 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 8080 -j DROP