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The authentication inside following ECALLs are bypassable using a manipulated OCALL return.
ECALL: ecall_change_master_password(), ecall_show_wallet(), ecall_add_item(), ecall_remove_item()
OCALL: ocall_load_wallet()
Reason:The ECALL accepts the master password. An attacker can bypass the password verification because it is depended on ocall_load_wallet() return (seal data). Using a malicious seal data, an attacker can easily bypass the authentication inside the enclave.

There is two double-free vulnerability in the enclave code which can lead to an information leak.
ECALLs: ecall_change_master_password() and ecall_add_item()
Code:

    sealed_data = (uint8_t*)malloc(sealed_size);
    sealing_status = seal_wallet(wallet, (sgx_sealed_data_t*)sealed_data, sealed_size);
    free(wallet); // first free
    if (sealing_status != SGX_SUCCESS) {
    	free(wallet);  // second free
        free(sealed_data);
	return ERR_FAIL_SEAL;
    }