It's Euonymus scale on a euonymus shrub. It IS a treatable problem but successful treatment depends on both product used and proper timing. I'd suggest you Google the topic and read up on some of the treatment recommendations published by the extension service universities.

The flip side of the coin is that some species of Euonymus are extremely susceptible to this insect problem and if you have it once, you will have it again. And heavily infested plants - like yours - often don't come back from the defoliation and dieback of a major infestation well. You might want to consider removing these and replacing with some other, less problematic plant.

Yikes, if those were mine, I'd think twice about keeping them. As GG said, these plants are highly prone to scale insect infestation. You'll have to deal with this the rest of your or its life!