B737 NG Captain reported an inflight upset occurred on descent into IAH when they encountered wake turbulence from a preceding A380.

Narrative

In the descent the aircraft began to get a rhythmic light chop. This got our attention and we both made the comment that this feels like wake turbulence. The flight had been completely smooth up until this point. A few seconds later the airplane started a slight roll to the left and recovered then rolled left again; this time to approximately 25 degrees. The F/O disconnected the autopilot; rolled wings level; and shallowed the descent rate. I verbalized UPSET at which point the recovery was complete as it was a short duration event. I advised ATC that we had a wake turbulence event and requested a half mile offset to the right. ATC gave us the offset and we continued the descent. ATC gave us a vector shortly after the offset; apparently to create more space with the aircraft in front of us. The Purser then called up and asked if there was going to any more turbulence. I asked if they were ok; to which she said everyone was good. I told her we were not expecting any more turbulence. I queried ATC on the type of aircraft we were following; they replied A380. The flight continued uneventfully.