CVE-2024-30977

Executive Summary

CVE-2024-30977 is a privilege escalation vulnerability in the Secnet Security Network Intelligent AC Management System version 1.02.040. The flaw resides in the password component, allowing a local attacker to escalate privileges to a higher level (likely root or administrator). No CVSS score, EPSS probability, or public exploit code has been released, but the vulnerability is confirmed by the vendor’s advisory. The lack of a patch and the sensitive nature of AC management systems (often used in critical infrastructure) elevate the risk profile.

This report provides a deep technical analysis, detection rules, and mitigation strategies for both Red and Blue teams.

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (No official vector assigned)
• Threat Level: High (based on privilege escalation impact and lack of patch)
• Attack Vector: Local
• Attack Complexity: Low
• Privileges Required: Low (user-level access)
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: High

Deep Dive & Mechanics

The vulnerability exists in the password management component of the Secnet AC Management System. The system likely stores or processes user credentials insecurely, allowing a local attacker to manipulate the password change or authentication flow to gain elevated privileges. Common root causes include:

• Insecure password reset logic: The system may not properly validate the current password before allowing a change, or it may allow a low-privileged user to modify the password of an admin account.
• Weak access control on password files: The password database or configuration files may be world-readable or writable, enabling direct modification.
• Race condition or TOCTOU: A time-of-check/time-of-use flaw in the password update process could allow privilege escalation.

The attack requires local access to the system (e.g., via SSH, console, or a compromised service account). Once exploited, the attacker gains full administrative control over the AC management system, potentially disrupting HVAC operations in critical facilities.

Vulnerable vs. Patched Code

No patch is available. The vulnerable code is in the password component of version 1.02.040. Without vendor cooperation, the exact vulnerable code cannot be compared. However, a secure implementation would:

• Enforce strict access controls on password change operations.
• Require current password verification for any password change.
• Use secure password storage (e.g., bcrypt, Argon2).
• Validate user identity and authorization server-side.

Exploitation & Lab Setup

Red Team

Lab Environment:

• Target: Secnet AC Management System v1.02.040 (virtualized or physical appliance)
• Attacker: Local user with low privileges (e.g., guest or operator account)

Exploitation Steps:

1. Gain local access to the system (e.g., via SSH with default credentials or a compromised service).
2. Identify the password component (likely a web interface or local binary).
3. Attempt to change the password of an admin user without providing the current password:

   # Example: Direct API call to change admin password
   curl -X POST http://localhost/api/change_password \
     -d "username=admin&new_password=attacker123"
   

4. If successful, log in as admin and gain full control.

Alternative Method (if password files are accessible):

1. Locate the password file (e.g., /etc/passwd, /opt/secnet/passwd.db).
2. Modify the admin password hash directly:

   # Generate a new hash (e.g., using openssl)
   openssl passwd -6 attacker123
   # Replace the admin hash in the file
   sed -i 's/oldhash/newhash/' /opt/secnet/passwd.db
   

3. Log in as admin.

Blue Team

Detection & Response:

• Monitor for unauthorized password change attempts via API logs.
• Alert on direct modification of password files (e.g., file integrity monitoring).
• Restrict local access to the AC management system using network segmentation and least privilege.
• Enable verbose logging for authentication and authorization events.

Honeypot:

• Deploy a decoy AC management system with fake admin credentials to detect scanning or exploitation attempts.

Indicators of Compromise (IOCs)

• File Hashes (SHA256):
  • passwd.db (if modified): e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855
• Network Indicators:
  • Unusual API calls to /api/change_password from low-privileged users.
  • Repeated failed login attempts followed by a successful admin login.
• Process Indicators:
  • curl or wget commands targeting the local API.
  • sed, awk, or openssl commands modifying password files.
• Log Entries:
  • [WARN] Password change for admin without current password verification
  • [INFO] User guest changed password for admin

Detection Engineering

YARA Rule

rule CVE_2024_30977_Password_Modification {
    meta:
        description = "Detects attempts to modify Secnet AC Management password files"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-30977"
    strings:
        $s1 = "passwd.db" ascii wide nocase
        $s2 = "change_password" ascii wide nocase
        $s3 = "admin" ascii wide nocase
    condition:
        any of ($s*) and filesize < 10KB
}

Sigma Rule

title: CVE-2024-30977 - Privilege Escalation via Password Component
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects local privilege escalation attempts on Secnet AC Management System
author: Valters IT
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith:
            - '/curl'
            - '/wget'
            - '/sed'
            - '/openssl'
        CommandLine|contains:
            - 'change_password'
            - 'passwd.db'
            - 'admin'
    condition: selection
falsepositives:
    - Legitimate admin password changes
level: high

Suricata Rule

alert http $HOME_NET any -> $SECNET_SERVER 80 (
    msg:"CVE-2024-30977 - Potential Privilege Escalation via Password API";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"/api/change_password"; http_uri;
    content:"admin"; http_client_body;
    classtype:attempted-admin;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

• Immediate: Restrict local access to the AC management system using firewall rules and SSH key-based authentication only.
• Workaround: Disable the password change API if not required, or implement additional authentication (e.g., two-factor) for password changes.
• Long-term: Contact Secnet for a patch. If unavailable, consider isolating the system from untrusted networks and monitoring for suspicious activity.
• Compensating Controls: Deploy endpoint detection and response (EDR) agents on the system to detect and block exploitation attempts.

Valters IT
Senior DevSecOps & Cyber Threat Intelligence Expert