Memos through 0.30.0 omits the 100.64.0.0/10 carrier-grade NAT address range from SSRF protection in its link-metadata fetcher, allowing unauthenticated attackers to bypass IP validation. Attackers can make the server request internal hosts in that range including cloud metadata services and read page titles and descriptions back.

Memos' webhook dispatch function safeDialContext (internal/webhook/webhook.go) resolves the target hostname via net.DefaultResolver.LookupHost and validates the resulting IPs against reserved ranges, but then dials net.JoinHostPort(host, port) using the original hostname rather than the already-validated IP address.