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A critical vulnerability, identified as CVE-2022-20763, has been discovered in the login authorization components of Cisco Webex Meetings, a popular video conferencing application used by businesses worldwide. This vulnerability could potentially allow an authenticated, remote attacker to inject arbitrary Java code into the application, potentially leading to data theft, unauthorized access to sensitive information, and other malicious activities. This blog post will provide an overview of the vulnerability, a code snippet to demonstrate the exploit, links to the original references, and in-depth exploit details.

What is CVE-2022-20763?

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CVE-2022-20763 is a security vulnerability affecting the login authorization components of Cisco Webex Meetings. This vulnerability is primarily caused by improper deserialization of Java code within login requests. A threat actor could exploit this vulnerability by sending malicious login requests to the Cisco Webex Meetings service, which could lead to the injection of arbitrary Java code and ultimately allow the attacker to take arbitrary actions within the Cisco Webex Meetings application.

Exploit Details

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To exploit this vulnerability, an attacker would first need to authenticate themselves with the Cisco Webex Meetings service. This could potentially be achieved by leveraging other vulnerabilities or through social engineering and phishing techniques. Once authenticated, the attacker would then craft a malicious Java Serialized Object (JSO) containing the arbitrary Java code they wish to inject. This code could include instructions to expose sensitive data, modify application settings, or execute other malicious activities.

The attacker would then send a login request to the Cisco Webex Meetings service with the malicious JSO embedded in the request. Due to the improper deserialization of Java code within the login request handling process, the arbitrary Java code would be executed, leading to the successful exploitation of the vulnerability.

Code Snippet

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Here's an example of a code snippet that demonstrates the exploit

import java.io.*;
import java.util.*;

public class CVE_2022_20763_Exploit {
  public static void main(String[] args) throws Exception {
    // Malicious Java Serialized Object (JSO) containing arbitrary Java code
    String maliciousJSO = "base64_encoded_malicious_JSO";

    // Decode the malicious JSO
    byte[] decodedJSO = Base64.getDecoder().decode(maliciousJSO);

    // Send the malicious login request to the Cisco Webex Meetings service
    sendLoginRequest(decodedJSO);
  }

  private static void sendLoginRequest(byte[] maliciousJSO) {
    // Implement the method to send the malicious login request
    // with the embedded malicious JSO to the Cisco Webex Meetings service
  }
}

Note that this is just a simple example to illustrate how the exploit could be carried out. The actual implementation may include more advanced techniques to evade detection and further compromise the application.

Original References

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1. Cisco Security Advisory: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-inject-U6DXfFbH
2. CVE Details: https://www.cvedetails.com/cve/CVE-2022-20763/
3. NVD (National Vulnerability Database): https://nvd.nist.gov/vuln/detail/CVE-2022-20763

Mitigation

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Cisco has released software updates that address this vulnerability, and all users are urged to apply these patches as soon as possible to prevent exploitation. Additionally, Cisco recommends implementing best practices for securing Cisco Webex Meetings, such as enabling multi-factor authentication, enforcing strong password policies, and providing user awareness training to help protect against social engineering tactics.

In conclusion, CVE-2022-20763 is a critical vulnerability found in the login authorization components of Cisco Webex Meetings, which could allow malicious actors to inject arbitrary Java code and perform unauthorized actions within the application. Organizations using Cisco Webex Meetings should be vigilant in applying patches provided by Cisco and following recommended security practices.

Timeline

Published on: 04/06/2022 19:15:00 UTC
Last modified on: 04/14/2022 15:11:00 UTC