Download iOS 13.3.1 (17D50) for iPhone XS

You will have to note that you can only restore signed IPSW firmware files using iTunes or 3utools.

❌ This IPSW firmware is not being Signed by Apple

Firmware Identifier iPhone11,2
iOS Version 13.3.1
Release Date 2020-01-28
Update Date 2020-01-22
Sha1sum
14e7d124f5c48f8562319bd30345cf70063676f4
Sha256sum
49acb4c790dbb3a6882cd5bd4d59a95c54ac6ba3524d3098e585f644ca855059
md5sum
75616afe5539c96d5d8f55027a21fb5f
Size 4.71 GB
FileName
iPhone11,2,iPhone11,4,iPhone11,6,iPhone12,3,iPhone12,5_13.3.1_17D50_Restore.ipsw
Status

Download IPSW (4.71GB) Check device info
Release Notes

It should be noted that these are the official release notes for the from Apple

iOS 13.3.1 includes bug fixes and improvements. This update:

For information on the security content of Apple software updates, please visit this website:

https://support.apple.com/kb/HT201222