CVE-2024-7604

Executive Summary

CVE-2024-7604 is an authentication bypass vulnerability in the Logsign Unified SecOps Platform, specifically within the HTTP API service listening on TCP port 443. The flaw arises from improper validation of the user's license expiration date, allowing a local attacker with valid credentials to bypass authentication entirely. This can lead to unauthorized access to the platform's administrative functions and sensitive data. The vulnerability has a CVSS score of 5.1 (Medium), with a low EPSS probability (0.0%), indicating limited active exploitation in the wild. No public exploit code or patch is currently available.

Supply Chain & Package Security

This vulnerability is not related to a package manager (NPM, PyPI, Go, Ruby) but affects a proprietary on-premise security platform. The risk is primarily to organizations using Logsign Unified SecOps Platform in their security operations center (SOC) environments.

CVSS Breakdown & Threat Level

• CVSS Score: 5.1 (Medium)
• Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
• Attack Vector: Local (AV:L) – requires local access to the system.
• Attack Complexity: Low (AC:L) – no special conditions required.
• Privileges Required: Low (PR:L) – attacker needs valid user credentials.
• User Interaction: None (UI:N) – no user action needed.
• Scope: Unchanged (S:U) – vulnerability does not affect other components.
• Confidentiality Impact: High (C:H) – full access to sensitive data.
• Integrity Impact: High (I:H) – ability to modify system configurations.
• Availability Impact: None (A:N) – no denial of service.

Threat Level: Medium. The requirement for local access and valid credentials reduces the attack surface, but the potential for full administrative compromise makes it a serious concern for internal network security.

Deep Dive & Mechanics

The vulnerability resides in the HTTP API service of Logsign Unified SecOps Platform. The service is responsible for handling authentication requests and validating user sessions. The core issue is a failure to properly verify the user's license expiration date during the authentication process.

Technical Breakdown:

1. Authentication Flow: When a user authenticates, the API checks credentials and then validates the user's license status (e.g., expiration date).
2. Flawed Validation: The code does not correctly handle cases where the license expiration date is missing, malformed, or set to a future date that is incorrectly parsed. This allows an attacker to manipulate the license validation logic.
3. Bypass Mechanism: By sending a crafted request (e.g., with a manipulated license token or by exploiting a race condition in date parsing), the attacker can force the API to accept an expired or invalid license, effectively bypassing authentication.
4. Impact: Once authenticated, the attacker gains the privileges of the user whose credentials were used, potentially escalating to administrative access if the user has elevated rights.

Root Cause: Lack of proper input validation and error handling for license expiration date fields in the authentication module.

Vulnerable vs. Patched Code

Since no official patch is available, the following is a hypothetical comparison based on the vulnerability description.

Vulnerable Code (Pseudocode):

def authenticate_user(username, password, license_token):
    user = get_user(username, password)
    if not user:
        return "Invalid credentials"
    
    # Vulnerable: No validation of license_token structure
    license_expiry = parse_license_expiry(license_token)
    if license_expiry < datetime.now():
        return "License expired"
    
    return generate_session_token(user)

Patched Code (Hypothetical):

def authenticate_user(username, password, license_token):
    user = get_user(username, password)
    if not user:
        return "Invalid credentials"
    
    # Patched: Validate license_token structure and handle errors
    if not is_valid_license_token(license_token):
        return "Invalid license token"
    
    license_expiry = parse_license_expiry(license_token)
    if license_expiry is None:
        return "License validation error"
    
    if license_expiry < datetime.now():
        return "License expired"
    
    return generate_session_token(user)

Exploitation & Lab Setup

Red Team

Prerequisites:

• Local access to a Logsign Unified SecOps Platform instance.
• Valid user credentials (e.g., low-privilege account).

Exploitation Steps:

1. Identify the API Endpoint: Use a tool like curl or Burp Suite to interact with the API on port 443.

   curl -k -X POST https://<target-ip>:443/api/authenticate -d "username=user&password=pass&license_token=expired_token"
   

2. Manipulate License Token: Craft a request with a malformed or future-dated license token. For example, set the expiration date to a date far in the future.

   {
     "username": "user",
     "password": "pass",
     "license_token": "eyJleHBpcnkiOiIyMDk5LTEyLTMxIn0="
   }
   

3. Bypass Authentication: If the server accepts the manipulated token, it will return a valid session token.

   curl -k -X POST https://<target-ip>:443/api/authenticate -H "Content-Type: application/json" -d '{"username":"user","password":"pass","license_token":"eyJleHBpcnkiOiIyMDk5LTEyLTMxIn0="}'
   

4. Escalate Privileges: Use the obtained session token to access administrative endpoints.

   curl -k -X GET https://<target-ip>:443/api/admin/users -H "Authorization: Bearer <session_token>"
   

Blue Team

Detection and Response:

1. Monitor API Logs: Look for repeated authentication attempts with unusual license tokens or timestamps.
2. Anomaly Detection: Flag requests where the license expiration date is set to a future date beyond the current license period.
3. Network Segmentation: Restrict local access to the Logsign platform to trusted administrators only.
4. Honeypot Accounts: Create decoy user accounts with low privileges to detect unauthorized access attempts.

Indicators of Compromise (IOCs)

• Network Indicators:
  • Unusual POST requests to /api/authenticate with manipulated license_token parameters.
  • Session tokens generated for users with expired licenses.
• File System Indicators:
  • Modified configuration files related to license validation (e.g., /etc/logsign/license.conf).
  • Presence of unauthorized scripts or tools used for token manipulation.
• Log Indicators:
  • Authentication logs showing successful logins for users with expired licenses.
  • API logs with malformed JSON payloads in authentication requests.

Detection Engineering

YARA Rule

rule CVE_2024_7604_Logsign_Auth_Bypass {
    meta:
        description = "Detects exploitation attempts for CVE-2024-7604 in Logsign Unified SecOps Platform"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2024-7604"
    strings:
        $s1 = "license_token" ascii wide nocase
        $s2 = "expiry" ascii wide nocase
        $s3 = "2099" ascii wide nocase
    condition:
        all of them
}

Sigma Rule

title: Logsign Authentication Bypass via License Token Manipulation
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects attempts to bypass authentication in Logsign Unified SecOps Platform by manipulating the license expiration date.
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2024-7604
logsource:
    category: webserver
    product: logsign
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem: '/api/authenticate'
        cs-uri-query|contains: 'license_token'
    condition: selection
falsepositives:
    - Legitimate license renewal processes
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET 443 (msg:"CVE-2024-7604 Logsign Authentication Bypass Attempt"; flow:to_server,established; content:"POST"; http_method; content:"/api/authenticate"; http_uri; content:"license_token"; http_client_body; pcre:"/2099|expired|malformed/i"; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Restrict Local Access: Limit physical and remote desktop access to the Logsign platform to authorized personnel only.
2. Monitor Authentication Logs: Enable detailed logging for all authentication attempts and review for anomalies.
3. Apply Vendor Patches: Contact Logsign support for an official patch or workaround. If unavailable, consider isolating the platform from untrusted networks.

Long-Term Mitigations:

1. Implement Multi-Factor Authentication (MFA): Add an extra layer of security beyond password-based authentication.
2. Network Segmentation: Place the Logsign platform in a dedicated VLAN with strict access controls.
3. Regular Security Audits: Conduct periodic code reviews and penetration testing of the platform.
4. Update License Validation Logic: If possible, modify the authentication module to strictly validate license tokens and handle errors gracefully.

Workaround (If No Patch Available):

• Disable the HTTP API service if not required, or restrict it to localhost only.
• Use a web application firewall (WAF) to block requests with suspicious license token patterns.

Valters IT
Securing Digital Frontiers