Cold$eal

Cold$eal is a packer for encrypting (sealing) malware. It contains some AV-evasion techniques as well as some sandbox-detection. It was developed by $@dok (aka Sadok aka Coldseal).

It was available as a cryptor service under the url coldseal.us and was later sold as a toolkit consisting of the cryptor and a custom made cryptostub including a FuD garantee backed by free update to the cryptostub. The payload was encrypted using RC4 and added to the cryptostub as a resource. The encryption key itself was stored inside the resource as well. Upon start the cryptostub would extract the key, decrypt the payload and perform a selfinjection using the now decrypted payload.

Note: The packed sample provided contains some harmless payload, while the unpacked sample is the bare cryptostub without a payload.