Reducing metadata leakage from software updates

Update: now you can do this with Tor Onion Services Many software update systems use code signing to ensure that only the correct software is downloaded and installed, and to prevent the code from being altered. This is an effective way to prevent the code from being modified, and because of that, software update systems often use plain, unencrypted HTTP connections for downloading code updates. That means that the metadata of what packages a machine has installed is available in plain text for any network observer, from someone sitting on the same public WiFi as you, to state actors with full network observation capabilities. [Read More]

Tweaking HTTPS for Better Security

The HTTPS protocol is based on TLS and SSL, which are standard ways to negotiate encrypted connections. There is a lot of complexity in the protocols and lots of config options, but luckily most of the config options can be ignored since the defaults are fine. But there are some things worth tweaking to ensure that as many connections as possible are using reliable encryption ciphers while providing forward secrecy. A connection with forward secrecy provides protection to past transactions even if the server’s HTTPS private key/certificate is stolen or compromised. [Read More]

Proposal for Secure Connection Notification on Android

A major problem of mobile applications being increasingly used over web-based applications, is that there is no standard established for notifying the user of the state of security on the network connection. With a web browser, the evolution of the “lock” icon when an HTTPS connection is made, has been one that evolved originally out of Netscape’s first implementation, to an adhoc, defact industry-standard way of letting the user know if their connection is secure. [Read More]

CACertMan app to address DigiNotar & other bad CA’s

As I expect many of you are aware, there was a major compromise to a Dutch Certificate Authority named “DigiNotar” recently, where they allowed SSL certs for domains like *, * and even * as well as *.*.com to be issued. It was brought up to the contribs of CyanogenMOD that they should probably remove the DigiNotar CA cert from the built-in Android OS keystore (located at /system/etc/security/cacerts.bks). Since they have 500k+ users, and can be more nimble than other ROM/device distributors, it was seen as a way to quickly address the problem, at least within their community. [Read More]