CVE-2022-30287 Exploiting Reflection Injection and Arbitrary Deserialization in Horde Groupware Webmail Edition through 5.2.22

A recent vulnerability, designated as CVE-2022-30287, has been identified in Horde Groupware Webmail Edition, versions up to and including 5.2.22. This article aims to provide a comprehensive explanation for both developers and users of how this vulnerability can be exploited to gain unauthorized access or control of an affected server. We will provide original references, code snippets, and detailed information about the specific exploit.

Background

Horde Groupware Webmail Edition is a popular open-source webmail system that provides organizations with an email platform, calendar, tasks, and contact management. Horde is often deployed in enterprise environments and, as a result, this vulnerability presents a significant concern.

Exploit Details

CVE-2022-30287 is a reflection injection attack that allows an attacker to instantiate a driver class within the Horde Groupware Webmail Edition. Once the attacker manages to instantiate a driver class, they can proceed to deserialize arbitrary PHP objects, leading to possible remote code execution (RCE) or other malicious activity.

The vulnerability exists in the Horde_Injector class that is responsible for instantiating objects of a specified class. Here is a simple example demonstrating the deserialization process:

class Horde_Injector {
public function createInstance($className) {
    return new $className();
  }
}

An attacker can manipulate this process by specifying a driver class and providing serialized data that contains malicious payloads. When the Horde_Injector class creates an instance of the malicious class, the payload gets executed, resulting in arbitrary deserialization.

To further illustrate the exploit, we can look at the following code snippet

class MaliciousDriver {
  public $serializedData = '...'; // Serialized data containing malicious payload
  
  public function __toString() {
    return unserialize($this->serializedData);
  }
}

$payload = new MaliciousDriver();
$payload->serializedData = '...'; // The attacker would provide their own serialized data here

$injector = new Horde_Injector();
$exploitedObject = $injector->createInstance($payload);

By instantiating the malicious driver class and passing serialized data with the payload, an attacker can execute arbitrary code or perform other malicious activities on the targeted webmail server.

For more details about CVE-2022-30287, the following resources provide valuable information

1. Original advisory published by the Horde Project: https://www.horde.org/advisories/2022-02-18-1
2. The official CVE-2022-30287 listing on the NIST National Vulnerability Database (NVD): https://nvd.nist.gov/vuln/detail/CVE-2022-30287

Mitigation and Recommendations

It is highly recommended that organizations using Horde Groupware Webmail Edition update their installations to version 5.2.23 or later, which contains a patch for the vulnerability. By implementing proper patch management, organizations can significantly reduce their risk.

Developers working with Horde should also follow best practices for secure coding, such as input validation, to prevent future vulnerabilities. Additionally, users should exercise caution when clicking on links and accessing attachments, as exploiting CVE-2022-30287 might involve using crafted links, emails, or messages that target the Horde Groupware Webmail Edition.

Conclusion

CVE-2022-30287 is a critical vulnerability affecting Horde Groupware Webmail Edition through version 5.2.22. The exploit allows attackers to perform a reflection injection attack, leading to arbitrary deserialization of PHP objects. By understanding the nature of this vulnerability and applying the necessary mitigations, organizations can better protect their webmail systems and sensitive data.

Timeline

Published on: 07/28/2022 22:15:00 UTC
Last modified on: 08/05/2022 16:16:00 UTC