Vietnam's second largest mobile network operator Mobifone was affected for 3 hours[1]. Now we know 3: UK, Japan and Vietnam. I'm sure it's possible track down the other 8.
Wow, Hong Kong's Smartone uses Ericsson and wasn't effected. I am surprised at how wide spread the problem is. How could Ericsson messed this up when the it has the biggest chance to grab business from Huawei.