CVE-2023-22527: Atlassian Confluence Data Center and Server Template Injection Vulnerability

CVE-2023-22527 is an unauthenticated OGNL template injection vulnerability affecting Atlassian Confluence Data Center and Server. It can allow an attacker to achieve remote code execution on vulnerable instances without needing valid credentials.

This matters for IT and security teams because the flaw requires no authentication, has been actively exploited, and is known to be used by ransomware operators. Unpatched systems face a realistic risk of full compromise, data theft, or operational disruption. Confirm all version and configuration details against the vendor advisory before acting.

How it works

The vulnerability is classified under CWE-74, improper neutralization of special elements in output used by a downstream component (injection). In Confluence Data Center and Server, this manifests as an OGNL template injection issue.

An unauthenticated attacker can abuse the flaw by submitting crafted input that the application processes as an OGNL expression. Successful injection can lead to remote code execution on the host. Exact request formats, parameters, or payloads are not detailed here; defenders must obtain those specifics only from the official vendor advisory and treat any public proof-of-concept material with caution until validated in a controlled environment.

Am I affected? How to find it in your systems

Atlassian Confluence Data Center and Server commonly run as internal or externally reachable collaboration platforms, often on dedicated application servers, virtual machines, or containerized environments within enterprise networks.

• Inventory by querying asset-management databases, CMDB records, and software-deployment tools for any Confluence Data Center or Server installations.
• Scan network ranges and application inventories for Confluence service banners, default ports, or known URL paths associated with the product.
• Compare installed versions and any relevant configuration settings against the affected product list published in the vendor advisory; do not assume a version is safe without that confirmation.
• Review access logs, web-application firewall logs, and host process telemetry for anomalous requests that attempt template or expression evaluation, unexpected outbound connections, or new processes spawned by the Confluence service account. Correlate any such activity with the timing of known exploitation campaigns.

How to remediate

Patch first. Apply the official vendor updates for Confluence Data Center and Server exactly as named and described in the Atlassian advisory for CVE-2023-22527. Verify successful installation and restart services according to vendor guidance.

After patching, harden the environment against this injection class: restrict network exposure of Confluence to only necessary internal clients, enforce least-privilege service accounts, enable any available application-level security controls that limit template evaluation, and keep the surrounding operating system and dependencies current. Re-validate the deployment against the vendor’s security configuration checklist.

If you can't patch immediately

CISA requires that organizations apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. Until the vendor update can be installed, reduce risk with these compensating controls:

• Network segmentation: isolate Confluence hosts from the broader enterprise and internet, allowing only explicitly authorized management and user traffic.
• Virtual patching or WAF rules: deploy signatures or custom rules that detect and block known patterns of OGNL or template-injection attempts; tune carefully to avoid false positives.
• Feature and access restrictions: disable any non-essential Confluence modules or endpoints if the vendor indicates they are involved, and require multi-factor authentication for all administrative interfaces.
• Heightened monitoring: increase logging verbosity for the Confluence process, forward logs to a SIEM, and alert on process creation, file-system changes, or network connections originating from the application.

These measures buy time but do not eliminate the vulnerability; schedule the official patch as the permanent fix.

If your data may have been exposed

Actively exploited vulnerabilities that enable remote code execution, especially those known to be used by ransomware groups, frequently result in data breaches or further lateral movement. If compromise is suspected, isolate affected hosts, preserve forensic evidence, and follow your incident-response plan. As a quick personal check, individuals can run a free exposure scan of their email address against known breach data sets to determine whether their credentials or personal information have already appeared in public dumps.