CVE-2025-44177: Wss Protop Path Traversal Vulnerability

CVE-2025-44177 Overview

A directory traversal vulnerability was discovered in White Star Software Protop version 4.4.2-2024-11-27, specifically in the /pt3upd/ endpoint. An unauthenticated attacker can remotely read arbitrary files on the underlying operating system using encoded traversal sequences. This vulnerability allows attackers to bypass directory restrictions and access sensitive system files without authentication.

Critical Impact

Unauthenticated remote attackers can read arbitrary files from the target system, potentially exposing sensitive configuration files, credentials, and other critical data.

Affected Products

• White Star Software Protop version 4.4.2-2024-11-27
• WSS Protop (cpe:2.3:a:wss:protop:4.4.2-2024-11-27:*:*:*:*:*:*:*)

Discovery Timeline

• 2025-07-09 - CVE-2025-44177 published to NVD
• 2025-07-18 - Last updated in NVD database

Technical Details for CVE-2025-44177

Vulnerability Analysis

This directory traversal vulnerability (CWE-22) exists in the /pt3upd/ endpoint of White Star Software Protop. The application fails to properly sanitize user-supplied input containing path traversal sequences before using it to access files on the server's filesystem. Attackers can exploit this by using encoded traversal sequences (such as ../ or URL-encoded variants like %2e%2e%2f) to escape the intended directory structure and access files anywhere on the system where the web server has read permissions.

The vulnerability is particularly concerning because it requires no authentication, allowing any remote attacker with network access to exploit it. The impact primarily affects confidentiality and integrity, enabling attackers to read sensitive files such as configuration files, password stores, application source code, and system files like /etc/passwd on Unix-based systems.

Root Cause

The root cause of this vulnerability is improper input validation in the /pt3upd/ endpoint. The application does not adequately sanitize or validate file path inputs before processing file operations. Specifically, the code fails to:

1. Canonicalize the requested file path before validation
2. Reject or neutralize directory traversal sequences (e.g., ../, ..%2f, %2e%2e/)
3. Enforce proper access controls to restrict file access to the intended directory

This allows attackers to craft malicious requests that traverse outside the web root or intended file directories.

Attack Vector

The attack vector is network-based, requiring no user interaction or prior authentication. An attacker can craft HTTP requests to the vulnerable /pt3upd/ endpoint containing encoded directory traversal sequences. By manipulating the file path parameter with sequences such as ../ (or URL-encoded equivalents), the attacker can navigate up the directory tree and access sensitive files on the underlying operating system.

For example, an attacker might request a path like /pt3upd/..%2f..%2f..%2f..%2fetc%2fpasswd to read the system's password file on a Linux system. A proof of concept demonstrating this vulnerability is available at the GitHub Gist Proof of Concept.

Detection Methods for CVE-2025-44177

Indicators of Compromise

• HTTP requests to /pt3upd/ containing path traversal sequences (../, ..%2f, %2e%2e/, etc.)
• Unusual access patterns to the /pt3upd/ endpoint from external IP addresses
• Web server logs showing requests attempting to access system files like /etc/passwd, /etc/shadow, or Windows system files
• Evidence of sensitive file contents in network traffic originating from the web server

Detection Strategies

• Deploy web application firewall (WAF) rules to detect and block path traversal patterns in HTTP requests
• Implement intrusion detection system (IDS) signatures for encoded directory traversal sequences targeting the /pt3upd/ endpoint
• Enable verbose logging on the Protop application and analyze logs for suspicious file access attempts
• Use file integrity monitoring on sensitive system files to detect unauthorized access

Monitoring Recommendations

• Monitor network traffic for HTTP requests containing encoded traversal sequences (%2e, %2f, %5c)
• Set up alerts for access attempts to the /pt3upd/ endpoint from untrusted networks
• Review web server access logs regularly for patterns indicative of directory traversal exploitation
• Implement behavioral analysis to detect anomalous file read operations by the web server process

How to Mitigate CVE-2025-44177

Immediate Actions Required

• Restrict network access to the /pt3upd/ endpoint using firewall rules or network segmentation
• Implement WAF rules to block requests containing directory traversal sequences
• If the /pt3upd/ endpoint is not required for operations, disable or remove it from the configuration
• Review system logs for evidence of prior exploitation attempts

Patch Information

No vendor patch information is currently available for this vulnerability. Organizations should monitor the ProtoP Official Website for security updates and patches. In the meantime, implement the recommended workarounds to reduce exposure risk.

Workarounds

• Apply strict input validation to reject any request containing path traversal sequences before processing
• Use a web application firewall (WAF) to filter malicious requests targeting the /pt3upd/ endpoint
• Implement network-level access controls to limit access to the Protop application from trusted networks only
• Run the Protop application with minimal filesystem permissions to limit the impact of successful exploitation

# Example: Block access to vulnerable endpoint using iptables (adjust as needed)
# Restrict access to only trusted IP ranges
iptables -A INPUT -p tcp --dport 80 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP