The SSRF vulnerability in Craft CMS affects versions >=5.0.0-RC1 before 5.10.6 and >=4.0.0-RC1 before 4.18.2. It exists in the GraphQL save<Volume>Asset mutation, which fetches URLs supplied by an attacker. The anti-SSRF validation function validateIp() does not account for Carrier-Grade NAT (100.64.0.0/10) or NAT64 (64:ff9b::/96) IP ranges, and critically, the IP validation occurs after the external request is already issued. This allows an attacker with limited GraphQL permissions to disclose internal HTTP content from CGNAT/NAT64 targets, force outbound GET requests to internal hosts including RFC1918 private addresses, loopback, and cloud metadata endpoints, and enumerate internal services.

An attacker with a GraphQL token scoped only to asset-creation permissions can exploit this SSRF vulnerability to access internal network resources that should be inaccessible externally. This includes internal HTTP content behind CGNAT and NAT64 IP ranges, private network hosts, loopback interfaces, and cloud metadata services. The vulnerability could lead to information disclosure and internal network reconnaissance. There is no indication of privilege escalation or remote code execution from the provided data.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Until a patch is available, restrict or monitor GraphQL tokens with asset-creation permissions to limit exposure. Avoid exposing the vulnerable GraphQL mutation to untrusted users. Follow vendor advisories for updates and apply official patches once released.