CVE-2025-2305: Path Traversal Vulnerability in File Download

CVE-2025-2305 Overview

A path traversal vulnerability has been identified in the file download functionality of an affected application server. This vulnerability allows unauthenticated users to download arbitrary files from the Linux server by manipulating file path parameters. The flaw stems from improper input validation (CWE-20) where user-supplied input is not adequately sanitized before being used to construct file paths.

Critical Impact

Unauthenticated attackers can exploit this path traversal vulnerability to access sensitive files from the Linux server, potentially exposing configuration files, credentials, source code, and other confidential data without requiring any authentication.

Affected Products

• Application server with vulnerable file download functionality (specific product details not disclosed in advisory)

Discovery Timeline

• 2025-05-16 - CVE-2025-2305 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2025-2305

Vulnerability Analysis

This path traversal vulnerability exists in the file download functionality of the affected application. The root cause is improper input validation where the application fails to properly sanitize user-supplied file path parameters before processing file download requests. An attacker can exploit this by injecting directory traversal sequences (such as ../) into file path parameters, allowing them to escape the intended directory and access files anywhere on the server that the application has read permissions for.

The vulnerability is particularly severe because it requires no authentication to exploit. Any remote attacker with network access to the vulnerable application can attempt to download arbitrary files from the underlying Linux server. This could lead to exposure of sensitive configuration files (such as /etc/passwd or application configuration files containing database credentials), private keys, source code, and other confidential information stored on the server.

Root Cause

The vulnerability is caused by improper input validation (CWE-20) in the file download functionality. The application fails to properly validate and sanitize user-supplied input before using it to construct file system paths. This allows attackers to bypass directory restrictions by including path traversal sequences in their requests, ultimately accessing files outside the intended download directory.

Attack Vector

The attack is conducted over the network without requiring any authentication or user interaction. An attacker sends a crafted HTTP request to the file download endpoint containing directory traversal sequences in the file path parameter. The vulnerable application processes this malicious input without proper sanitization, resulting in the server retrieving and returning files from arbitrary locations on the file system.

A typical exploitation scenario involves an attacker modifying the file path parameter to include sequences like ../../../../etc/passwd to traverse up from the web application directory and access sensitive system files. The scope of accessible files depends on the privileges of the application server process.

Detection Methods for CVE-2025-2305

Indicators of Compromise

• HTTP requests to file download endpoints containing path traversal sequences (../, ..%2f, %2e%2e/, etc.)
• Unusual file access patterns in application or system logs showing access to files outside normal application directories
• Access attempts to sensitive system files such as /etc/passwd, /etc/shadow, or configuration files from web application processes
• Elevated network traffic from the application server potentially indicating data exfiltration

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block requests containing path traversal patterns in URL parameters and request bodies
• Configure intrusion detection systems (IDS) to alert on HTTP requests with directory traversal signatures
• Review application logs for requests containing encoded or plaintext traversal sequences
• Monitor file access patterns for the application server process to detect reads of files outside expected directories

Monitoring Recommendations

• Enable verbose logging for the file download functionality to capture all requested file paths
• Implement real-time log analysis to detect traversal patterns in incoming requests
• Set up alerts for access attempts to sensitive system directories from web application processes
• Deploy endpoint detection and response (EDR) solutions to monitor file access behavior on application servers

How to Mitigate CVE-2025-2305

Immediate Actions Required

• Review and restrict access to the vulnerable file download functionality until a patch is available
• Implement network-level access controls to limit who can reach the affected application
• Deploy WAF rules to block requests containing path traversal sequences
• Audit application logs to identify any potential exploitation attempts

Patch Information

Refer to the Cirosec Security Advisory SA-2025-003 for detailed remediation guidance and vendor-specific patch information. Organizations should monitor this advisory for updates regarding official patches from the affected vendor.

Workarounds

• Implement strict input validation on all file path parameters, rejecting any input containing traversal sequences
• Configure the application to use a whitelist approach, only allowing downloads of files from an explicitly defined list
• Ensure the application server runs with minimal file system permissions, limiting the scope of accessible files
• Consider implementing a chroot jail or containerization to isolate the application from the broader file system

# Example WAF rule configuration for blocking path traversal
# ModSecurity rule to detect directory traversal attempts
SecRule REQUEST_URI|ARGS|ARGS_NAMES "@rx (\.\.\/|\.\.\\)" \
    "id:1001,\
    phase:2,\
    deny,\
    status:403,\
    log,\
    msg:'Path Traversal Attack Detected'"