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This is a private blog by Jens Lechtenbörger.

Jens Lechtenbörger

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Creative Commons License
Unless explicitly stated otherwise, my posts on this blog are licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.

Certificate Pinning for GNU/Linux and Android

Previously, I described the dismal state of SSL/TLS security and explained how certificate pinning protects against man-in-the-middle (MITM) attacks; in particular, I recommended GnuTLS with its command line tool gnutls-cli for do-it-yourself certificate pinning based on trust-on-first-use (TOFU). In this post, I explain how I apply those ideas on my Android phone. In a nutshell, […]

Certificate Pinning for GNU Emacs

GNU Emacs is where is spend most of my computer time. Using Emacs, I’m writing texts in general and this post in particular, I’m programming, I’m reading RSS feeds and news articles, I’m reading and writing e-mails. Emacs is highly customizable and extensible which is great, in general. However, in the past Emacs valued convenience […]

Certificate Pinning with GnuTLS in the Mess of SSL/TLS

Lots of modern communication is “protected” from spying eyes and other criminals via an Internet standard called Transport Layer Security (TLS) or its outdated predecessor Secure Sockets Layer (SSL). In the following, I’m using the term “SSL/TLS” to refer to both of them. In a nutshell, SSL/TLS is a mess. It’s security has been, can […]