Map: Toxic Bay
Scenario: I got frozen while I was sprinting. I stopped to sprint while I was frozen. The enemy icewitch attacked me and thus pushed me over a cliff from the rocks and I fell down on the ice while I was unfreezing. After the landing I had super high increased walk(!) speed. Without exaggeration it felt like 3 times sprint speed! I also was able to jump as high as a berserker can do with his skill. I don't use any amulets (-> no double amulet bug).
My teammate confirmed that it looks the same from the outside point of view. Like a Speedhack and Low Gravity.
My attackspeed was not influenced. I was able to heal normally while walking. I was able to pick up the box for the machine and carry it with super high walkspeed. Everything was normal except the high walk speed and highjump.

This behaviour remained after death and respawn. I was able to end it by sprinting. After sprinting I had the normal walkspeed and the normal jump again.

I don't know if it is that easy to reproduce on purpose. I don't know which effects caused the bug. Maybe freeze while sprint? Maybe sprint while frozen on ice? Maybe sprint while frozen midair over ice and walk on after unfreeze? I never saw it on another person and had it myself the first time now, so I don't think it is affecting many players.