CVE-2023-50436: Critical Vulnerability Discovered in Couchbase Server - Leaking Encoded Admin Credentials in Diag.log File

A severe security vulnerability has been found in Couchbase Server versions before 7.2.4, which can lead to the leakage of encrypted administrator credentials into the diag.log file. This vulnerability has been assigned the CVE identifier CVE-2023-50436. The earliest Couchbase Server version affected is 7.1.5. In this article, we'll discuss the details related to the vulnerability, how it can be exploited, and the steps you can take to safeguard your deployments against potential risks.

Vulnerability Details

Couchbase Server is an open-source, distributed, NoSQL document-oriented database that can scale horizontally, enabling developers to effortlessly manage and store their data. The vulnerability discovered in Couchbase Server is related to the logging mechanism. The ns_server, which is the primary management component, logs admin credentials in an encoded form in the diag.log file. This log file may contain sensitive data that can be exploited by an attacker to gain unauthorized access to the system. The following code snippet shows how the encoded admin credentials can be extracted from the log file:

import re
import base64

logfile_path = '/path/to/diag.log'

with open(logfile_path, 'r') as logfile:
    data = logfile.read()
    
pattern = r'"encoded_credentials": "(.*?)"'
encoded_credentials = re.findall(pattern, data)

for creds in encoded_credentials:
    decoded_creds = base64.b64decode(creds).decode()
    print("Decoded credentials: '{}'".format(decoded_creds))

Exploit and Risks

An attacker with access to the affected Couchbase Server instance can obtain and decode the encoded admin credentials present in the diag.log file, as shown in the code snippet above. This unauthorized access to sensitive information can be used to gain control over the Couchbase system, perform arbitrary actions, or compromise data integrity and availability. In worst-case scenarios, this could lead to data breaches or unauthorized access to other systems, if the same credentials are used elsewhere.

Mitigation and Patching

To fix this vulnerability and keep your Couchbase Server safe from threats, all affected users should upgrade immediately to Couchbase Server version 7.2.4 or later. The updated Couchbase versions no longer log the ns_server admin credentials in the diag.log file, thus resolving the vulnerability.

You can download the latest Couchbase Server version from their official website: Couchbase Downloads

Additionally, users should monitor and restrict access to their log files and system resources. Proper access control and restrictive file permissions can help minimize the risks associated with information leakage.

References

- Couchbase Server: Official Website
- Couchbase Server: Release Notes
- NIST: National Vulnerability Database (CVE-2023-50436)

Conclusion

CVE-2023-50436 is a critical vulnerability that affects Couchbase Server instances before version 7.2.4, causing ns_server admin credentials to be leaked in the diag.log file. To stay protected, users should upgrade their Couchbase Server instances to the latest version, restrict access to sensitive files, and maintain proper access control mechanisms. Keep monitoring for security updates and follow best practices to ensure the security of your database deployments.

Timeline

Published on: 02/29/2024 01:42:00 UTC
Last modified on: 02/29/2024 13:49:47 UTC