`ls` causes Segmentation Fault on a specific directory
Most likely you have some library installed in there that gets loaded instead of the system ones when you execute a command in there and it is binary incompatible with the commands in your system. It's probably something related to glibc or so.
You can confirm this by running LD_TRACE_LOADED_OBJECTS=1 ls and examining the output to see if it includes any of the files in the current directory.