CVE-2025-23209 remediation guide
Craft CMS
Craft is a flexible, user-friendly CMS for creating custom digital experiences on the web and beyond. This is an remote code execution (RCE) vulnerability that affects Craft 4 and 5 installs where your security key has already been compromised. Anyone running an unpatched version of Craft with a compromised security key is affected. This vulnerability has been patched in Craft 5.5.8 and 4.13.8. Users who cannot update to a patched version, should rotate their security keys and ensure their privacy to help migitgate the issue.
Identify the affected asset
Confirm whether Craft CMS is installed, record the deployed version and installation path, and identify exposed interfaces.
- Record the product name, package or appliance identifier, and installed version.
- Identify internet-facing, administrative, API, and internal access paths.
- Preserve the pre-change configuration and relevant service logs.
Validate the affected-version match
Compare the deployed version with the affected range: >= 5.0.0-RC1, < 5.5.5, >= 4.0.0-RC1, < 4.13.8, > 4.0.0 < 4.13.8, > 5.0.0 < 5.5.8, 4.0.0, 5.0.0. Treat incomplete inventory results as unresolved.
Prioritize with independent signals
CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog. Combine this signal with asset criticality, exposure, compensating controls, and business impact.
Apply supported remediation
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Verify the result
Confirm the resulting version, service health, authentication and access paths, monitoring coverage, and relevant security logs.
- Confirm the expected version and package state.
- Run a functional health check for critical service paths.
- Review authentication, error, application, and security monitoring logs.
- Reassess exposure if the supported fix cannot be applied.
Operational boundary
This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.