CVE-2025-52352

Executive Summary

CVE-2025-52352 exposes a critical authentication bypass vulnerability in the Aikaan IoT management platform (version v3.25.0325-5-g2e9c59796). The platform provides a configuration to disable user sign-up in distributed deployments by hiding the sign-up option on the login page UI. However, the sign-up API endpoint remains publicly accessible and functional, allowing unauthenticated attackers to register accounts via APIs even when the feature is disabled. This leads to unauthorized access to admin portals, violating intended access controls. The vulnerability has a CVSS score of 0.0 (likely uncalculated or placeholder), but based on the impact, it is assessed as critical with a vector of AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. No public exploit code or patch is currently available.

Supply Chain & Package Security

This vulnerability is not related to a specific package manager (NPM, PyPI, Go, Ruby). It affects the Aikaan IoT management platform, which is a proprietary software solution. No supply chain implications are identified at this time.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – The vulnerability is exploitable remotely over the network.
• Attack Complexity (AC): Low (L) – No special conditions or complex steps are required.
• Privileges Required (PR): None (N) – No authentication is needed to trigger the vulnerability.
• User Interaction (UI): None (N) – No user action is required.
• Scope (S): Unchanged (U) – The vulnerable component and the impacted component are the same.
• Confidentiality (C): High (H) – Unauthorized access to admin portals can lead to full data exposure.
• Integrity (I): High (H) – Attackers can modify system configurations and data.
• Availability (A): High (H) – Attackers could disrupt IoT device management.

Threat Level: Critical. The vulnerability allows unauthenticated account registration, leading to full administrative access. Given the IoT context, this could compromise thousands of devices.

Deep Dive & Mechanics

The Aikaan IoT management platform includes a configuration option to disable user sign-up in distributed deployments. This is intended to prevent unauthorized users from creating accounts. The platform hides the sign-up button on the login page UI when this feature is disabled. However, the underlying API endpoint responsible for user registration (e.g., /api/v1/signup or similar) remains active and does not check the configuration flag. This means an attacker can directly call the API to register a new account, bypassing the UI restriction.

The vulnerability is a classic case of missing authorization check on the server side. The UI restriction is purely cosmetic and does not enforce the policy at the API level. This is a common security anti-pattern where client-side controls are used instead of server-side enforcement.

Root Cause: The sign-up API endpoint does not validate whether the sign-up feature is enabled before processing the request. The configuration flag is only checked on the frontend, not in the backend logic.

Attack Flow:

1. Attacker identifies the Aikaan platform (e.g., via Shodan or direct scanning).
2. Attacker sends a POST request to the sign-up API endpoint with valid registration data (username, password, email).
3. The API processes the request and creates a new user account, potentially with elevated privileges (e.g., admin role).
4. Attacker logs in with the newly created account and gains unauthorized access to the admin portal.

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

// Frontend: hides sign-up button
if (config.disableSignUp) {
    document.getElementById('signup-btn').style.display = 'none';
}

// Backend: no check for config flag
app.post('/api/v1/signup', (req, res) => {
    const { username, password, email } = req.body;
    // Directly creates user without checking config
    db.createUser(username, password, email);
    res.status(200).json({ message: 'User created' });
});

Patched Code (Conceptual):

// Backend: checks config flag before processing
app.post('/api/v1/signup', (req, res) => {
    if (config.disableSignUp) {
        return res.status(403).json({ error: 'Sign-up is disabled' });
    }
    const { username, password, email } = req.body;
    db.createUser(username, password, email);
    res.status(200).json({ message: 'User created' });
});

The patch adds a server-side check of the disableSignUp configuration flag before processing the registration request. This ensures that even if the API is called directly, the policy is enforced.

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Target running Aikaan IoT management platform v3.25.0325-5-g2e9c59796.
• Network access to the target (e.g., via Shodan or internal network).

Exploitation Steps:

1. Reconnaissance: Identify the target's sign-up API endpoint. Common endpoints include /api/v1/signup, /api/register, or /user/register. Use a tool like Burp Suite or curl to probe.
2. Craft Request: Send a POST request to the sign-up endpoint with valid registration data. Example using curl:

   curl -X POST https://target.com/api/v1/signup \
     -H "Content-Type: application/json" \
     -d '{"username":"attacker","password":"P@ssw0rd!","email":"attacker@example.com"}'
   

3. Verify Account: If the request returns a success message (e.g., {"message":"User created"}), the account is created.
4. Login: Use the created credentials to log in to the admin portal.
5. Escalate Privileges: If the account is not automatically admin, look for privilege escalation vectors (e.g., modifying the role parameter in the registration request).

No public exploit code is available. The above steps are based on the vulnerability description.

Blue Team (Detection & Defense)

Detection:

• Monitor for POST requests to sign-up API endpoints (e.g., /api/v1/signup, /api/register).
• Alert on successful account creation events when sign-up is supposed to be disabled.
• Look for anomalous registration patterns (e.g., multiple registrations in a short time, registrations from unusual IPs).

Defense:

• Immediately apply the server-side patch (check config flag before processing registration).
• If patching is not possible, block access to the sign-up API endpoint at the network level (e.g., using a WAF or firewall rule).
• Implement additional authentication controls, such as IP whitelisting for registration endpoints.
• Conduct a full audit of all API endpoints to ensure client-side controls are not relied upon for security.

Indicators of Compromise (IOCs)

• Network IOCs:

  • POST requests to /api/v1/signup or similar endpoints from external IPs.
  • Successful HTTP 200 responses from sign-up endpoints when sign-up is disabled.
  • Login attempts from newly created accounts shortly after registration.

• System IOCs:

  • Unexpected user accounts in the Aikaan platform database.
  • Log entries showing account creation events during times when sign-up should be disabled.
  • Unauthorized access to admin portal features.

• File IOCs:

  • No specific file-based IOCs identified.

Detection Engineering

YARA Rule

rule CVE_2025_52352_Aikaan_Signup_Bypass {
    meta:
        description = "Detects exploitation attempts of CVE-2025-52352 - Aikaan IoT sign-up bypass"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-52352"
    strings:
        $api_endpoint = "/api/v1/signup" nocase
        $json_body = "{\"username\":" nocase
        $success_msg = "User created" nocase
    condition:
        any of ($api_endpoint) and any of ($json_body) and any of ($success_msg)
}

Sigma Rule

title: Aikaan IoT Sign-up API Bypass
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects POST requests to Aikaan sign-up API endpoints, indicating potential exploitation of CVE-2025-52352
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: accesslog
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem:
            - '/api/v1/signup'
            - '/api/register'
            - '/user/register'
    condition: selection
falsepositives:
    - Legitimate sign-up attempts if sign-up is intentionally enabled
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-52352 Aikaan IoT Sign-up API Bypass Attempt"; flow:to_server; content:"POST"; http_method; content:"/api/v1/signup"; http_uri; nocase; content:"username"; http_client_body; nocase; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Patch: Apply the server-side patch that checks the disableSignUp configuration flag before processing registration requests. If no official patch is available, implement a custom fix by modifying the backend code.
2. Network Block: Block access to the sign-up API endpoint at the network level (e.g., using a WAF rule or firewall ACL) until a patch is applied.
3. Audit: Review all existing user accounts for unauthorized registrations. Remove any suspicious accounts.

Long-term Recommendations:

• Implement a security review process for all API endpoints to ensure server-side enforcement of access controls.
• Adopt a "deny by default" approach for API endpoints, requiring explicit configuration to enable registration.
• Conduct regular penetration testing and vulnerability scanning.
• Monitor for similar vulnerabilities in other parts of the platform.

Workarounds:

• If patching is not possible, consider disabling the sign-up API endpoint entirely by removing or commenting out the route in the web server configuration.
• Use a reverse proxy (e.g., Nginx) to block requests to the sign-up endpoint.

Valters IT