Critical CVE-2023–22515 — Confluence Data Center & Server Privilege Escalation Vulnerability

Introduction

In the dynamic realm of cybersecurity, staying ahead of vulnerabilities is paramount. The recent discovery of CVE-2023–22515, a Critical Privilege Escalation vulnerability in Confluence Data Center and Server, has sent shockwaves through the IT community. This article delves into the details of this vulnerability, its severity, affected versions, and how to protect your systems from potential exploitation.

CVE-2023–22515: A Critical Threat

Atlassian, the developer of Confluence, rates the severity of CVE-2023–22515 as critical with a CVSS score of 10, the highest possible score. This score reflects the severity of the vulnerability, emphasizing the urgency required to address it. The vulnerability pertains to Broken Access Control, which can lead to unauthorized privilege escalation.

Proof of Concept (POC)

A concise Proof of Concept (POC) to detect the vulnerability is demonstrated here:

cat file.txt | while read host; do
  curl -skL "http://$host/setup/setupadministrator.action" | grep -i "<title>Setup System Administrator" && echo $host "is VULN";
done

Affected Versions:

The vulnerability impacts numerous versions of Confluence Data Center and Confluence Server, including but not limited to:

8.0.0 to 8.5.1

Fixed Versions:

To mitigate this threat, Atlassian recommends upgrading your affected installations to the following fixed versions or any later version:

8.3.3 or later

8.4.3 or later

8.5.2 (Long Term Support release) or later

These fixed versions include the necessary patches to protect your system from this vulnerability.

Protecting Your Systems: What You Need To Do

Upgrade to a Fixed Version:

Upgrade your Confluence installation to one of the recommended fixed versions. You can find detailed instructions for the upgrade process on Atlassian’s website.

Additionally, if your Confluence instances are accessible to the public internet with user authentication, consider restricting external network access until the upgrade is complete. This step reduces the potential attack surface.

Threat Detection:

Atlassian cannot confirm if your instances have been compromised. Collaborate with your security team to examine all affected Confluence instances for any signs of compromise. Possible indicators of compromise include:

Unexpected members in the confluence-administrators group

Newly created user accounts that you cannot account for

Requests to /setup/*.action in network access logs

The presence of /setup/setupadministrator.action in an exception message in atlassian-confluence-security.log within the Confluence home directory

If you suspect a compromise, it is crucial to act promptly. Reach out to Atlassian’s support for assistance in recovering and securing your instance.

Shodan Search for Confluence Instances:

For organizations concerned about their Confluence instances exposed to the internet, Shodan can be a valuable tool for identifying potential targets. To find such instances using Shodan, you can use dorks, which are search queries that help you filter results. For example, if you want to search for Confluence instances in the United Kingdom (GB), you can use a dork like:

Confluence country:"GB"

This query will filter Shodan results to show only Confluence instances in the United Kingdom. Remember, Shodan may return numerous results, so exercise caution and ensure you have legitimate reasons to access the systems you identify.

In Conclusion: Protecting Your Confluence Instances

In the face of CVE-2023–22515, vigilance and swift action are the keys to safeguarding your Confluence Data Center and Server instances. Heed Atlassian’s recommendations, upgrade your systems, and monitor for potential compromises. By following these guidelines, you can mitigate the risks associated with this critical vulnerability and keep your systems secure. Stay safe and secure in the digital landscape!