The SHSH (Signature HaSH) blob is a digital signature Apple uses to control iOS versions. When you click "Flash" or "Save SHSH," 3uTools acts as a middleman, sending a request to Apple’s TSS (Ticket Signing Server).

"Alright, the direct approach then," Leo said. He knew that if 3uTools couldn't fetch the blobs automatically, it usually meant the firmware version he was aiming for was no longer being . He opened a browser and checked the signing status; sure enough, the window had closed an hour ago.