The ECB penguin is an excellent example of how ECB can be misused. However, people who see this example do not realize how easy such a mistake can be avoided. Like I have said, if the penguin were not a noiseless drawing, but a photography with a small amount of noise, there would have been no leaking of the image through the ECB encryption.
For this SPICE application, ECB was a bad choice anyway.
Like I have said, ECB can be used alone only with values that do not repeat or which have a negligible probability of repetition, like random numbers. Otherwise, ECB must be used only as a component of a more complex mode of operation, e.g. in combination with a PRNG that is combined with the text stream either only before encryption, or both before and after encryption.
However, when encrypting English text or text written in a programming language or something like a SPICE model, which is similar to a program, the use of ECB is very seldom a mistake sufficient to allow decryption. The chances of exploiting ECB for a successful decryption increase only when you have huge amounts of encrypted text, e.g. gigabytes or terabytes.
When you would monitor something like the communications of some spies, even a very small amount of information about the content of their messages may still be of some use, so if they use ECB, that would be a capital mistake for them.
On the other hand even if you would be able to decrypt a half of a SPICE model, it is very unlikely that this would be useful in any way. With SPICE models, what you need is the complete set of parameters, which is something that you cannot obtain when you do not have access to the physical devices that are modeled, to be able to measure them and extract the parameters from the measurements.
Even if you have 80% of the parameters, they are still useless, because that does not allow you to guess which are the missing parameters, which would enable you to model accurately the behavior of a device.
