OpenSSH jump-host and file-transfer

This article was inspired by a previous post on my personal blog: https://www.freeture.ch/?p=815 Intro OpenSSH is a great tool, everybody knows that (even Microsoft). It's commonly used to securely take control or copy a bunch of files to or from remote machines. Another common scenario is to have a machine between two networks that acts as … Continue reading OpenSSH jump-host and file-transfer

OpenSSH hardening for cloud machine – Two-factor authentication – part 2

I enthusiastically use two-factor authentication whenever possible because static passwords aren't the best mechanism to mitigate risk... Traditional passwords are vulnerable to social engineering, key-loggers, malwares and—especially as computers become ever faster—to cracking. With many popular websites providing two-factor authentication (TFA, T-FA or 2FA), why shouldn't you add two-factor authentication to OpenSSH that run on the … Continue reading OpenSSH hardening for cloud machine – Two-factor authentication – part 2

OpenSSH hardening for cloud machine – part 1

SSH is often required to access Linux machines that run on the Cloud infrastructure. SSH is perfect to keep confidentiality and integrity of data exchanged between two networks and systems. However, this service exposes a new attack surface  that could be exploited by a threat agent. The aim of this post is to provide tips on how to … Continue reading OpenSSH hardening for cloud machine – part 1

Don’t run a Tor router and a hidden service from the same connection!

Today's post covers Tor hidden services and their anonymity.  In the first few paragraphs I will provide some basic, high level information on the Tor network and then talk about a way to uncover the real location of some anonymous hidden services. For those not familiar with it: Tor allows anyone to proxy their network traffic* … Continue reading Don’t run a Tor router and a hidden service from the same connection!