Swarms 6.8.1 Server-Side Request Forgery via DNS Rebinding Bypass

Swarms through 6.8.1, fixed in commit 8b0fc9e, contains a server-side request forgery vulnerability in the _is_safe_url function that fails to validate hostnames through DNS resolution, allowing attackers to bypass the blocklist. Attackers can supply user-controlled image or audio URLs that resolve to private, loopback, or metadata addresses to reach internal services and exfiltrate credentials.