CVE-2022-23123: Netatalk Sensitive Information Disclosure Vulnerability Exploitation and Mitigation Techniques

A recently discovered vulnerability, CVE-2022-23123, has been found to impact certain installations of Netatalk, exposing critical information to potential attackers. Due to the absence of required authentication, this vulnerability grants remote attackers access to sensitive data on affected installations. The vulnerability originates from the getdirparams method, arising from insufficient validation of user-supplied data and leading to a read past the end of an allocated buffer. As a result, this vulnerability can be exploited along with other existing vulnerabilities to execute arbitrary code with root privileges.

In this post, we'll be providing an overview of CVE-2022-23123, as well as detailing exploitation methods and providing links to relevant resources.

Exploit Details

The vulnerability in question exists within the getdirparams method, specifically due to the insufficient validation of user-supplied data, which can lead to a read past the end of an allocated buffer. This can be exploited by an attacker to gain unauthorized access to sensitive information on affected Netatalk installations.

Example Code Snippet

int getdirparams(AFPConfig *config, char *dir, struct path *path) {
  ...
  if (memcmp(dir, "../", 3) == ) {
    dir += 3;
  }
  ...
  if (path) {
    memcpy(path->st_path.data, dir, path->st_path.len);
  } else {
    ...
  }        
  ...
  return ;
}

In this example, the code assumes that the dir parameter value does not contain any "../" substring. However, it fails to validate this assumption correctly. As a result, an attacker can supply a specially crafted dir value containing "../" substrings to read sensitive data beyond the allocated buffer.

Related References and Sources

1. CVE-2022-23123 - National Vulnerability Database (NVD)
2. Zero Day Initiative Advisory - ZDI-CAN-15830
3. Netatalk Official Website

Mitigation and Solutions

It is essential for users of affected Netatalk installations to apply patches or implement workarounds to protect their system from this vulnerability. Netatalk users are encouraged to upgrade to the latest version, which addresses the vulnerability and renders the associated risks null and void.

For those who cannot immediately update, consider implementing workarounds such as network segmentation or restricting access to Netatalk services to only trusted users and devices. Additionally, enabling strong authentication and ensuring proper access control measures are in place can mitigate the impact of this vulnerability.

Conclusion

CVE-2022-23123 is a significant vulnerability that affects certain Netatalk installations, granting attackers unauthorized access to sensitive information. By exploiting this vulnerability, malicious parties can obtain potentially sensitive information, making it crucial for users to take immediate action to safeguard their systems. By implementing proper mitigations and staying informed of the latest security updates, users can effectively minimize the risk of this vulnerability posing a threat to their installations.

Timeline

Published on: 03/28/2023 19:15:00 UTC
Last modified on: 05/17/2023 01:15:00 UTC