Craft CMS versions 4.5.0‑RC1 through 4.16.18 and 5.0.0‑RC1 through 5.8.22 contain a time‑of‑check time‑of‑use flaw in the GraphQL Asset mutation. The validation routine resolves a DNS name before sending the HTTP request, allowing an attacker to serve the name with one IP during validation and a different IP during the actual request. This DNS rebinding bypasses the SSRF protection that had targeted only IPv6 endpoints in a prior fix, enabling a published SSRF vulnerability to reach any internal host or cloud metadata service.

The affected product is Craft CMS, with impacted releases from the listed 4.* and 5.* branches. Versions earlier than 4.16.19 and 5.8.23 are vulnerable, while patch versions 4.16.19 and 5.8.23 contain the necessary remediation. The issue is relevant to sites that expose the GraphQL API and assign asset‑mutation rights to users or misconfigure the public schema with write capabilities.

The CVSS score of 7.0 indicates high severity, yet the EPSS score remains below 1 % and the vulnerability is not yet in the CISA Known Exploited Vulnerabilities catalog. Exploitation requires that an attacker can use the GraphQL asset mutation to edit or create assets in a volume; for many installations this privilege is granted to authenticated users or public schema users when misconfigured. Given the TOCTOU nature of the flaw, a successful attack could grant internal network reconnaissance or the ability to reach cloud metadata services, potentially exposing sensitive tokens or enabling further lateral movement.