CVE-2023-22515: Confluence Data Center Auth Bypass Flaw

CVE-2023-22515 Overview

CVE-2023-22515 is a critical authentication bypass vulnerability in Atlassian Confluence Data Center and Server that allows unauthenticated remote attackers to create unauthorized administrator accounts and gain full access to Confluence instances. This broken access control vulnerability has been actively exploited in the wild and is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog.

Atlassian was made aware of this issue through reports from customers where external attackers exploited this previously unknown vulnerability in publicly accessible Confluence instances. Atlassian Cloud sites accessed via atlassian.net domains are not affected by this vulnerability as they are hosted by Atlassian.

Critical Impact

Unauthenticated remote attackers can create unauthorized Confluence administrator accounts and completely compromise affected Confluence Data Center and Server instances. This vulnerability is actively exploited in the wild.

Affected Products

• Atlassian Confluence Data Center (versions prior to patched releases)
• Atlassian Confluence Server (versions prior to patched releases)
• Note: Atlassian Cloud sites (atlassian.net domains) are NOT affected

Discovery Timeline

• October 4, 2023 - CVE-2023-22515 published to NVD
• October 24, 2025 - Last updated in NVD database

Technical Details for CVE-2023-22515

Vulnerability Analysis

CVE-2023-22515 represents a severe broken access control vulnerability in Atlassian Confluence Data Center and Server. The vulnerability allows unauthenticated attackers to bypass authentication mechanisms entirely and create new administrator accounts on publicly accessible Confluence instances. Once an attacker has administrator-level access, they can perform any administrative action including accessing sensitive data, modifying content, installing malicious plugins, and potentially achieving remote code execution on the underlying server.

The vulnerability is particularly dangerous because it requires no user interaction and can be exploited remotely over the network without any prior authentication. This makes it trivial for attackers to compromise any publicly accessible Confluence instance that has not been patched.

Root Cause

The root cause of CVE-2023-22515 is improper input validation (CWE-20) combined with broken access control. The vulnerability exists in the setup functionality of Confluence, which fails to properly validate and restrict access to administrative setup endpoints. Attackers can manipulate requests to these endpoints to create new administrator accounts without proper authentication, effectively bypassing the access control mechanisms that should protect such sensitive functionality.

Attack Vector

The attack vector for CVE-2023-22515 is network-based and requires no authentication or user interaction:

1. Initial Access: The attacker identifies a publicly accessible Confluence Data Center or Server instance
2. Exploitation: The attacker sends specially crafted HTTP requests to the vulnerable setup endpoints
3. Account Creation: The vulnerable endpoint allows the attacker to create a new administrator account
4. Compromise: With administrator credentials, the attacker gains full control of the Confluence instance
5. Post-Exploitation: The attacker can access sensitive data, install backdoors, or leverage the access for further attacks

The vulnerability allows attackers to manipulate setup-related endpoints to bypass authentication checks, enabling unauthorized administrator account creation. Detailed technical exploitation information is available in the Packet Storm Exploit Report.

Detection Methods for CVE-2023-22515

Indicators of Compromise

• Unexpected administrator accounts created in Confluence that were not authorized by IT staff
• Suspicious HTTP requests to setup-related endpoints (e.g., /setup/ paths) in web server access logs
• Unfamiliar or unauthorized Confluence plugins installed on the system
• Anomalous login activity from administrator accounts, especially from unexpected IP addresses or geolocations

Detection Strategies

• Review Confluence administrator user accounts for any unexpected or unauthorized additions created after the vulnerability disclosure
• Analyze web server access logs for requests to Confluence setup endpoints, particularly POST requests to administrative paths
• Monitor for failed and successful authentication attempts to administrator accounts from unusual sources
• Implement network intrusion detection rules to identify exploitation attempts targeting this vulnerability

Monitoring Recommendations

• Enable comprehensive audit logging in Confluence to track all administrative actions and account modifications
• Configure alerts for new administrator account creation events within Confluence
• Deploy web application firewall (WAF) rules to block suspicious requests to setup endpoints
• Monitor for outbound network connections from Confluence servers that may indicate post-exploitation activity

How to Mitigate CVE-2023-22515

Immediate Actions Required

• Immediately apply the latest security patches from Atlassian to all affected Confluence Data Center and Server instances
• Review all administrator accounts in Confluence and remove any unauthorized or suspicious accounts
• If patching is not immediately possible, restrict network access to Confluence instances by blocking public internet access
• Audit Confluence for any unauthorized changes, malicious plugins, or suspicious content modifications

Patch Information

Atlassian has released security patches to address CVE-2023-22515. Organizations should immediately upgrade their Confluence Data Center and Server instances to the latest patched versions. Detailed patching information is available in the Atlassian Security Advisory and the Atlassian FAQ for CVE-2023-22515. Additional technical details can be found in the Atlassian JIRA Issue CONFSERVER-92475.

Workarounds

• Block external network access to Confluence instances until patches can be applied by restricting access to trusted internal networks only
• Implement web application firewall rules to block access to vulnerable setup endpoints
• If the Confluence instance does not require public access, move it behind a VPN or restrict access via IP whitelisting
• Monitor for and immediately revoke any unauthorized administrator accounts that may have been created

# Example: Block access to setup endpoints using iptables (temporary mitigation)
# Restrict access to Confluence from trusted networks only
iptables -A INPUT -p tcp --dport 8090 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 8090 -j DROP

# Example: Apache/Nginx reverse proxy rule to block setup endpoints
# Add to your web server configuration
# Apache:
# <Location "/setup">
#     Deny from all
# </Location>
# Nginx:
# location /setup {
#     deny all;
#     return 403;
# }