The Appointment Hour Booking Plugin for WordPress is a popular plugin used by many websites to allow users to book appointments and services. Unfortunately, a critical vulnerability affecting this plugin has been discovered, making all versions up to and including 1.3.72 vulnerable to CSV (Comma Separated Values) Injection attacks. In this long-read post, we will discuss the vulnerability, provide a code snippet to demonstrate the exploit, and direct you to the original references and resources for further information. This vulnerability has been assigned the CVE-2022-4034 identifier.

Vulnerability Details

The CVE-2022-4034 vulnerability allows unauthenticated attackers to inject malicious content during the booking creation process. This injected content can then be included in a CSV file when the site administrator exports the booking details. If the administrator opens this malicious file on a system with a vulnerable configuration, it could lead to arbitrary code execution.

The vulnerability exists because the plugin does not properly sanitize user input during the booking creation process, allowing attackers to enter malicious payloads in fields like the user's name, address, or phone number.

Exploit Code Snippet

Here's an example of a malicious payload that an attacker could inject during the booking creation process:

=cmd|' /C calc'!A

This payload, when entered into a vulnerable field, would attempt to launch the calculator application (calc.exe) when the exported CSV file is opened on a Windows system using Microsoft Excel.

Steps to Exploit the Vulnerability:

1. Identify a WordPress site that uses the Appointment Hour Booking plugin with a version vulnerable to CVE-2022-4034.
2. Create a new booking using the site's appointment booking form.
3. Inject the malicious payload (like the one shown above) into one of the input fields.
4. Wait for the site administrator to export the booking details as a CSV file.
5. The administrator opens the exported CSV file in a vulnerable application (e.g., Microsoft Excel), and the payload is executed.

Original References:

To learn more about the CVE-2022-4034 vulnerability and obtain information on how to protect your WordPress site, please refer to the following resources:

1. Official CVE details: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-4034
2. National Vulnerability Database (NVD) entry: https://nvd.nist.gov/vuln/detail/CVE-2022-4034
3. Appointment Hour Booking Plugin's Official Page: https://wordpress.org/plugins/appointment-hour-booking/

Mitigation and Remediation:

The developers of the Appointment Hour Booking plugin have released a patch to address this vulnerability. It's highly recommended to update the plugin to the latest version immediately to mitigate the risk of exploitation. Additionally, site administrators should always be cautious when opening exported CSV files, especially those containing user-generated content.

In conclusion, the CVE-2022-4034 vulnerability in the Appointment Hour Booking plugin presents a severe security risk for WordPress websites utilizing this plugin. Site owners and administrators should take immediate action to update the plugin and follow recommended security practices to avoid falling victim to CSV Injection attacks.

Timeline

Published on: 11/29/2022 21:15:00 UTC
Last modified on: 12/01/2022 22:04:00 UTC