Detection Framework

JSteg-Shell:
When using RC4 encryption contains 32-bit footer.
RC4 encryption is restricted to 40-bit keys.
32 bits certainty.

Outguess:
32-bit header:
16 bits containing seed,
16 bits containing message length.
All values are possible:
Allowed seed can be restrained,
Minimum message length can be checked.
Stegbreak retrieves up to 512 bytes of data after header to check for randomness.
Too many candidate passwords, dictionary attack currently not feasible.