CVE-2024-7601

Executive Summary

CVE-2024-7601 is a high-severity path traversal vulnerability in the Logsign Unified SecOps Platform, specifically within the HTTP API service (default port 443). The flaw resides in the data_export_delete_all endpoint, where user-supplied paths are not properly validated before being used in file deletion operations. An authenticated remote attacker can exploit this to delete arbitrary files on the system, potentially causing a denial of service, data loss, or system compromise. The vulnerability is assigned a CVSS score of 7.1 (High) and is classified under CWE-22 (Improper Limitation of a Pathname to a Restricted Directory). No public proof-of-concept (PoC) or exploit code has been released, and the vendor has not yet provided a patch. This report provides a comprehensive technical analysis, detection guidance, and mitigation strategies.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
• Base Score: 7.1 (High)
• Attack Vector: Network (AV:N) – Exploitable remotely.
• Attack Complexity: Low (AC:L) – No special conditions required.
• Privileges Required: Low (PR:L) – Authentication is required, but low-privileged accounts can exploit.
• User Interaction: None (UI:N) – No user action needed.
• Scope: Unchanged (S:U) – Vulnerability does not affect other components.
• Confidentiality Impact: None (C:N) – No data exfiltration.
• Integrity Impact: High (I:H) – Arbitrary file deletion corrupts system integrity.
• Availability Impact: High (A:H) – Deletion of critical files can cause denial of service.

Threat Level: High. While authentication is required, the low complexity and high impact make this a critical risk for any organization using Logsign Unified SecOps Platform.

Deep Dive & Mechanics

The vulnerability exists in the data_export_delete_all endpoint of the Logsign HTTP API. The endpoint is designed to delete exported data files, but it fails to sanitize user-supplied path parameters. An attacker can supply a path traversal sequence (e.g., ../../../etc/passwd) to delete files outside the intended directory.

Root Cause: The application uses a user-supplied path directly in file system operations (e.g., unlink() or remove()) without validating that the resolved path stays within an allowed base directory. This is a classic path traversal vulnerability (CWE-22).

Attack Flow:

1. Attacker authenticates to the Logsign API (e.g., via a valid session token or credentials).
2. Attacker sends a crafted HTTP request to the data_export_delete_all endpoint with a path parameter containing ../ sequences.
3. The server processes the request and deletes the file at the traversed path.
4. The attacker can delete critical system files (e.g., /etc/shadow, /var/log/syslog, application binaries) causing denial of service or system instability.

Impact: An attacker can delete arbitrary files as the root user, leading to:

• Denial of service (deleting critical system files).
• Data loss (deleting logs, databases, or configuration files).
• Potential privilege escalation (deleting authentication files or binaries).

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code pattern is described below. A patched version would implement proper path validation.

Vulnerable Code (Conceptual):

@app.route('/api/data_export_delete_all', methods=['POST'])
def delete_export():
    path = request.json.get('path')
    # No validation - directly uses user-supplied path
    os.remove(path)
    return jsonify({'status': 'deleted'})

Patched Code (Conceptual):

import os
from pathlib import Path

ALLOWED_BASE = Path('/var/logsign/exports')

@app.route('/api/data_export_delete_all', methods=['POST'])
def delete_export():
    user_path = request.json.get('path')
    # Resolve and validate path
    full_path = (ALLOWED_BASE / user_path).resolve()
    if not str(full_path).startswith(str(ALLOWED_BASE.resolve())):
        return jsonify({'error': 'Invalid path'}), 400
    if not full_path.exists():
        return jsonify({'error': 'File not found'}), 404
    os.remove(str(full_path))
    return jsonify({'status': 'deleted'})

Exploitation & Lab Setup

Red Team (Offensive)

Prerequisites:

• Access to a Logsign Unified SecOps Platform instance (e.g., a lab VM).
• Valid authentication credentials (low-privileged user).

Exploitation Steps:

1. Authenticate to the Logsign API and obtain a session token.
2. Craft a POST request to the data_export_delete_all endpoint with a malicious path.
3. Example using curl:

   curl -k -X POST \
     -H "Authorization: Bearer <token>" \
     -H "Content-Type: application/json" \
     -d '{"path": "../../../etc/passwd"}' \
     https://target/api/data_export_delete_all
   

4. Verify deletion by checking if the file is removed (e.g., ls -la /etc/passwd).

Advanced Exploitation:

• Delete SSH authorized keys to lock out administrators.
• Delete system binaries (e.g., /bin/bash) to cause denial of service.
• Delete log files to cover tracks.

Blue Team (Defensive)

Detection:

• Monitor API logs for requests to /api/data_export_delete_all with suspicious path parameters (e.g., containing ../).
• Use file integrity monitoring (FIM) to alert on unexpected deletions of critical files.
• Deploy a WAF rule to block path traversal patterns in API requests.

Honeypot:

• Create a fake sensitive file (e.g., /tmp/honeypot.txt) and monitor for its deletion.

Lab Setup:

• Deploy a Logsign instance in an isolated environment.
• Create a low-privileged user account.
• Use a network sniffer (e.g., tcpdump) to capture exploit traffic.

Indicators of Compromise (IOCs)

• Network:
  • HTTP POST requests to /api/data_export_delete_all with path parameters containing ../ or absolute paths.
  • Unusual outbound traffic from the Logsign server (e.g., data exfiltration attempts).
• File System:
  • Unexpected deletion of files outside the expected export directory (e.g., /etc/passwd, /var/log/syslog).
  • Missing critical system files or binaries.
• Logs:
  • API access logs showing repeated failed or successful deletion requests.
  • System logs (e.g., auth.log) showing authentication attempts from suspicious IPs.

Detection Engineering

YARA Rule

rule CVE_2024_7601_Logsign_Path_Traversal {
    meta:
        description = "Detects path traversal attempts in Logsign API requests"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-7601"
    strings:
        $path_traversal = /\.\.\/|\.\.\\|\.\.%2f|\.\.%5c/
        $api_endpoint = "/api/data_export_delete_all"
    condition:
        $api_endpoint and $path_traversal
}

Sigma Rule

title: Logsign Path Traversal Attempt
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects path traversal attempts in Logsign API requests
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2024-7601
logsource:
    category: webserver
    product: logsign
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem: '/api/data_export_delete_all'
        cs-uri-query|contains: 
            - '../'
            - '..\\'
            - '%2e%2e%2f'
            - '%2e%2e%5c'
    condition: selection
falsepositives:
    - Legitimate use of relative paths within allowed directory (unlikely)
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2024-7601 Logsign Path Traversal Attempt";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"/api/data_export_delete_all"; http_uri;
    pcre:"/(\.\.\/|\.\.\\|%2e%2e%2f|%2e%2e%5c)/i";
    reference:cve,2024-7601;
    classtype:attempted-admin;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the endpoint if not required: Block access to /api/data_export_delete_all via firewall or reverse proxy.
2. Restrict API access to trusted IPs only.
3. Review user permissions – Ensure only necessary users have API access.

Long-term Fix:

• Apply vendor patch when available.
• Implement input validation and path sanitization (see patched code example).
• Use a Web Application Firewall (WAF) with rules to block path traversal patterns.

Workaround:

• If patching is not possible, consider removing the vulnerable endpoint or replacing it with a safer alternative.

Monitoring:

• Enable detailed logging for all API requests.
• Set up alerts for path traversal patterns in logs.

This report was generated by Valters IT DevSecOps & CTI Division.
Valters IT – Securing Your Digital Frontier.