CVE-2025-20156: Lap escalation of the privilege in Rest API of Cisco Meeting Management

Details

• CVE ID: CVE-2025-20156.

• CVSS Score: 9.9 (Critical).

• Vendor: Cisco.

• Affected Product: Cisco Meeting Management REST API.

• Disclosure Date: 01/22/2025.

• Description: The vulnerability allows a remote attacker with low privileges, who is authenticated, to escalate privileges to an administrator on the affected device.

Overview

On January 22, 2025, Cisco released software updates to fix a critical privilege escalation vulnerability in Cisco Meeting Management, tracked as CVE-2025-20156. This vulnerability has a CVSS score of 9.9 out of 10, allowing an attacker to perform remote actions with low privileges and then escalate privileges to an administrator on the affected devices.

An attacker can exploit this vulnerability by sending API requests to a specific endpoint. A successful exploit could allow the attacker to gain administrative control over Cisco meeting management.

Cause of the vulnerability

• Cisco Meeting Management does not perform adequate authorization checks when users send requests through the REST API.

• A specific REST API endpoint allows users with low privileges to send requests to access or modify resources that should only be accessible by administrators.

Affected Versions

• Cisco Meeting Management version 3.9

• Cisco Meeting Management version 3.8 and earlier versions

Technical Attack Details

Attack Vector

• The attacker needs access to the application's REST API to send API requests.

• The attacker can send commands or change data.

• Perform malicious actions like changing system configurations, managing nodes, or facilitating further attacks.

Attack Stages

1. Reconnaissance Stage:

   • Initially, the attacker will log into the system with a low-privilege account. In recorded campaigns, the accounts used are typically standard User accounts.

2. Intrusion Stage:

   • After successfully logging into the system, the attacker can begin gathering information to find exploitable REST API endpoints.

   • Some ways to perform information gathering:

     • Analyze public API documentation (if available).

     • Use network monitoring tools (like Wireshark) to see how API requests are made.

     • Use REST API tools (like Postman, Burp Suite, or curl) to test suspicious endpoints.

   • After obtaining the information, the attacker will send a forged REST API request to the vulnerable endpoint, using low-privilege login credentials.

   • A malicious API payload sent will contain two main components:

     • Change user role: Upgrade the current account to administrator privileges.

     • Edit system configuration: Modify or overwrite important configuration parameters.

   • Example of a payload executed if an endpoint can handle user roles without checking permissions

     

     \=> If this request is accepted without checking permissions, the system will upgrade the user role of userId: 12345 to "admin".

     \=> Then, the attacker will have access and control over the entire system.

3. Exploitation Stage:

   • Finally, after successfully exploiting, the attacker confirms that their account has been upgraded or that the system configuration has been changed.

   • Once they have high-level privileges on the compromised Cisco devices, the attacker can:

     • Perform actions reserved for administrators.

     • Deploy malware, steal data, or sabotage system configurations.

Exploitation Tools

• Burp Suite: For analyzing and spoofing API requests.

• Postman: For sending and testing REST API requests.

• Wireshark: For collecting information about API traffic.

Recommendations

1. Update Software:

   • If you are using Cisco Meeting Management version 3.9, update to version 3.9.1, where this vulnerability has been fixed.

   • For versions 3.8 and earlier, it is recommended to upgrade to the latest available version to ensure security.

2. Security Information Monitoring:

   • Regularly check Cisco security bulletins to stay updated on the latest vulnerabilities and patches.

3. Restrict API Access:

   • Ensure that only necessary users have access to the REST API and apply strong access controls.

4. System Monitoring:

   • Monitor unusual activities in the system and set up alerts for suspicious behavior to detect potential attacks early.

Summary

CVE-2025-20156 is a critical security vulnerability in the REST API of Cisco Meeting Management, allowing a remote attacker, who is authenticated with low privileges, to escalate privileges to an administrator level on affected devices. This vulnerability exists due to improper enforcement of privileges for REST API users. An attacker can exploit it by sending API requests to a specific endpoint, thereby gaining administrator-level control over management by Cisco Meeting Management.

Reference

1. Cisco Fixes Critical Privilege Escalation Flaw in Meeting Management (CVSS 9.9)

2. Cisco Meeting Management REST API Privilege Escalation Vulnerability

3. NVD - CVE-2025-20156