We are continuously working to improve the security of Ledger devices. As our business grows, we will accelerate our work identifying opportunities to improve the security of our services and products. This will involve a shift from substantial updates, months apart, to a more regular flow of software updates. Today we are making available Nano S firmware 1.4.2, following a recent update to 1.4.1. The latest release includes a series of minor but meaningful updates. As such, this update is recommended for all Ledger Nano S users, and is compatible for every firmware versions.

Firmware 1.4.2 step by step upgrade guide

Key changes

User PIN code's start number is now always randomized
Each recovery word's first letter is now always randomized
Improvement of the interaction between microcontroller (MCU) and secure element to remove confusing error message
Verification & checks of installed applications
Improved dashboard responsiveness

Please note that if you’ve already updated your Nano S to firmware 1.4.1, the update from 1.4.1 to 1.4.2 should be much easier & quicker than from 1.3.x
For more information:

Guide: How to update my Ledger Nano S with the firmware 1.4.2
FAQ: Frequently Asked Questions regarding the firmware 1.4.2