sep_panic — Secure Enclave
The Secure Enclave Processor panicked. According to iFixit, either the communication lines between the CPU and the chip from which the SEP reads its data are damaged, or the firmware/iOS is corrupted (the preferred lead if the fault follows an iOS downgrade).
iPhone
Logic board (SEP link) — or corrupted firmware/iOS (after a downgrade)
Low confidenceVerified sourceSecure Enclave
First check
DFU restore to the latest signed version; if the fault returns, logic board diagnosis.