Endpoint Detection and Response inaccessible using putty - Error "Couldn't agree a key exchange algorithm"

Products

• Endpoint Detection and Response

Issue/Introduction

Endpoint Detection and Response inaccessible using putty - Error "Couldn't agree a key exchange algorithm"

Environment

EDR Version : 4.6.5

 

Cause

SSH or WinSCP connection to EDR Appliance fails with a message : 
Couldn't agree a key exchange algorithm (available: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521, diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,)

The Couldn't agree a key exchange algorithm is expected behavior with older version of PuTTy or PuTTy integrated solutions like WinSCP.

 

Resolution

To resolve this issue, upgrade PuTTy to a version to 0.65 or later from http://www.putty.org/.