Renaming the middle part of a filename

Hi, I need to rename about 300 files from the example below and I'm struggling to get my head around it

From

ABC_DEF_1\23456789_2020_03_04

to

ABC_DEF_1\2345XXXX_2020_03_04

Each file has the constant ABC_DEF_1\2345NNNN_2020_03_04 but the NNNN part is different on all files, I just need to make the NNNN part in to XXXX

Many thanks

Replace method using Regular Expressions...

Replace: ^.{14}\K\d{4}
with: XXXX

Skips 14 characters starting at the beginning of the filename and then replaces the following 4 digits.

Reply to #2:

Many thanks, you've saved me a very tedious job, much appreciated