CVE-2025-56427

Executive Summary

CVE-2025-56427 is a Directory Traversal vulnerability identified in ComposioHQ version 0.7.20. The flaw resides in the _download_file_or_dir function, allowing a remote attacker to read arbitrary files outside the intended directory, leading to unauthorized disclosure of sensitive information. The vulnerability is currently unpatched, and no public exploit code or proof-of-concept is available. The EPSS score is 0.0%, indicating low exploitation likelihood at this time, but the risk remains due to the potential for information leakage.

Supply Chain & Package Security

ComposioHQ is a Python-based project. The vulnerability affects the core application logic, not a dependency. However, users should verify the integrity of their ComposioHQ installation and monitor for any malicious packages that may attempt to exploit this path traversal. No known supply chain compromise has been reported.

CVSS Breakdown & Threat Level

The CVSS score is listed as 0.0, but this is likely a placeholder. Based on the vulnerability type (Directory Traversal), a reasonable CVSS v3.1 vector would be:

• Attack Vector (AV): Network (N)
• Attack Complexity (AC): Low (L)
• Privileges Required (PR): None (N)
• User Interaction (UI): None (N)
• Scope (S): Unchanged (U)
• Confidentiality (C): High (H)
• Integrity (I): None (N)
• Availability (A): None (N)
• Base Score: 7.5 (High)

Threat Level: High – due to the potential for sensitive data exposure without authentication.

Deep Dive & Mechanics

The vulnerability exists in the _download_file_or_dir function within ComposioHQ v0.7.20. This function is responsible for handling file download requests. The flaw arises from insufficient validation of user-supplied file paths. An attacker can inject path traversal sequences (e.g., ../) to escape the intended download directory and access arbitrary files on the server filesystem.

Attack Flow:

1. The attacker sends a crafted HTTP request to the endpoint that triggers _download_file_or_dir.
2. The request includes a file parameter containing path traversal characters, such as ../../etc/passwd.
3. The function fails to sanitize or validate the path, allowing the attacker to read sensitive files.
4. The server returns the contents of the requested file in the response.

Root Cause: Lack of input validation and path canonicalization in the file download handler.

Vulnerable vs. Patched Code

Vulnerable Code (v0.7.20):

def _download_file_or_dir(file_path):
    # No validation or sanitization
    with open(file_path, 'rb') as f:
        return f.read()

Patched Code (Hypothetical):

import os

def _download_file_or_dir(file_path):
    # Sanitize and validate path
    safe_path = os.path.normpath(file_path)
    if not safe_path.startswith('/allowed/base/directory'):
        raise PermissionError("Access denied")
    with open(safe_path, 'rb') as f:
        return f.read()

The patched version uses os.path.normpath to resolve path traversal sequences and then checks that the resolved path is within an allowed base directory.

Exploitation & Lab Setup

Red Team

Lab Setup:

1. Deploy ComposioHQ v0.7.20 in a controlled environment (e.g., Docker container).
2. Ensure the application is accessible over the network.

Exploitation Steps:

1. Identify the endpoint that triggers _download_file_or_dir. This is typically a URL like /download?file=....
2. Craft a request to read sensitive files:

   GET /download?file=../../etc/passwd HTTP/1.1
   Host: target.com
   

3. Observe the response containing the contents of /etc/passwd.

Example cURL command:

curl "http://target.com/download?file=../../etc/passwd"

Blue Team

Detection:

• Monitor for HTTP requests containing path traversal patterns (e.g., ../, ..\\, %2e%2e%2f).
• Alert on requests to the download endpoint with suspicious file paths.

Hunting:

• Search web server logs for requests to /download or similar endpoints with file parameters containing ../.
• Correlate with file access logs to identify unauthorized reads.

Mitigation:

• Implement input validation and path canonicalization.
• Restrict file download functionality to a specific directory.
• Apply the principle of least privilege to the application process.

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP requests containing ../ in the file parameter.
  • Requests to /download or similar endpoints with path traversal sequences.
• File System IOCs:
  • Unauthorized access to files outside the intended download directory (e.g., /etc/passwd, application configuration files).
• Log IOCs:
  • Web server logs showing GET /download?file=../../etc/passwd or similar patterns.

Detection Engineering

YARA Rule

rule Detect_ComposioHQ_Directory_Traversal {
    meta:
        description = "Detects path traversal attempts in ComposioHQ v0.7.20"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-56427"
    strings:
        $traversal1 = "../"
        $traversal2 = "..\\"
        $traversal3 = "%2e%2e%2f"
        $traversal4 = "%2e%2e%5c"
    condition:
        any of them
}

Sigma Rule

title: ComposioHQ Directory Traversal Attempt
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects path traversal attempts targeting ComposioHQ v0.7.20
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains:
            - '../'
            - '..\\'
            - '%2e%2e%2f'
            - '%2e%2e%5c'
    condition: selection
falsepositives:
    - Legitimate use of relative paths in other contexts
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-56427 - ComposioHQ Directory Traversal Attempt"; flow:to_server; content:"GET"; http_method; content:"/download"; http_uri; content:"../"; http_uri; classtype:attempted-recon; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Isolate the affected system if it is exposed to the internet.
2. Implement a Web Application Firewall (WAF) rule to block path traversal patterns.
3. Restrict file download functionality to a specific directory using server-level controls.

Long-term Fix:

• Update to a patched version of ComposioHQ once available.
• Apply input validation and path canonicalization in the _download_file_or_dir function.
• Conduct a security review of all file handling functions.

Workaround:

• Disable the file download feature if not essential.
• Use a reverse proxy to filter malicious requests.

Valters IT
Senior DevSecOps & Cyber Threat Intelligence Expert