Android Tips

Android is a very secure and robust operating system out of the box. This post will be less of a “hardening guide”, but more of a non-exhaustive list of tips when it comes to buying and using Android phones. Android Devices Recommended Phones Google Pixel phones are the only devices I would recommend for purchase. Pixel phones have stronger hardware security than any other Android devices currently on the market, due to proper AVB support for third-party operating systems and Google’s custom Titan security chips acting as the Secure Element....

July 22, 2022 · 18 min · 3664 words · Tommy

Android VPN Leakage with Secondary User Profiles

Update: This is no longer reproducible on Android 13 QPR1 and Android 14 Developer Preview 1. Before We Start… I have been aware of this issue for awhile now (since at least Android 11), though I have not done enough testing to see what actually causes the leak nor do I have any workaround at the moment. My guess is that applications which launch early when you log into a secondary profile can bypass the VPN killswitch....

October 10, 2022 · 2 min · 327 words · Tommy

Badness Enumeration

Badness enumeration is the concept of making a list of known bad actors and attempting to block them. While it seems intuitive at first glance, badness enumeration should not be relied on for privacy or security. In many cases, it actually does the exact opposite and directly harms the user. This post will attempt to explain why badness enumeration as a concept is flawed and give some examples of its failings in practice....

July 27, 2022 · 6 min · 1183 words · Tommy

Choosing Your Android-Based Operating System

Android is a secure operating system that has strong app sandboxing, Verified Boot (AVB), and a robust permission control system. When you buy an Android phone, the device’s default operating system often comes with invasive integration with apps and services that are not part of the Android Open-Source Project. An example of such is Google Play Services, which has irrevocable privileges to access your files, contacts storage, call logs, SMS messages, location, camera, microphone, hardware identifiers, and so on....

July 18, 2022 · 9 min · 1723 words · Tommy

Commercial VPN Use Cases

Virtual Private Networks are a way of creating a protected and private network over the open Internet. It was originally designed to provide remote access to an internal corporate network. However, in recent years, it has also been used by commercial VPN companies to hide their clients’ real IP address from third-party websites and services. Should I use a VPN? Yes, unless you are already using Tor. A VPN does two things: shifting the risks from your Internet Service Provider to itself and hiding your IP from a third-party service....

July 19, 2022 · 5 min · 896 words · Tommy

Desktop Linux Hardening

Linux is not a secure desktop operating system. However, there are steps you can take to harden it, reduce its attack surface, and improve its privacy. Before we start… Some of the sections will include mentions of unofficial builds of packages like linux‑hardened, akmod, hardened_malloc, and so on. These are not endorsements — they are merely to show that you have options to easily obtain and update these packages. Using unofficial builds of packages means adding more parties to trust, and you have to evaluate whether it is worth doing so for the potential privacy/security benefits or not....

August 17, 2022 · 25 min · 5173 words · Tommy

NetworkManager Trackability Reduction

MAC address randomization Note that Ethernet connections can still be tracked via switch ports, and WiFi connections can be broadly localized by access point. Furthermore, MAC address spoofing and randomization depends on firmware support from the interface. Most modern network interface cards support the feature. There are three different aspects of MAC address randomization in NetworkManager, each with their own configuration flag: WiFi scanning [device] wifi.scan-rand-mac-address=yes WiFi connections [connection] wifi.cloned-mac-address=<mode> Ethernet connections [connection] ethernet....

September 4, 2022 · 4 min · 772 words · WfKe9vLwSvv7rN

ProtonVPN IP Leakage on Linux and Workaround

Before We Start… I sent Proton an email regarding this issue in late August 2022 and was told they are working on fixing it, though it will take some time as it requires some architectural changes in how the killswitch works. The Leak Ideally, when implementing a killswitch, a VPN client should drop all connections on non-VPN interfaces except when the connection is to the VPN provider’s servers. This is necessary to prevent accidental leaks, at least by unprivileged applications....

October 8, 2022 · 3 min · 560 words · Tommy

Using Lokinet on Qubes OS

Lokinet is an Internet overlay network utilizing onion routing to provide anonymity for its users, similar to Tor network. This post will provide a quick (and non exhaustive) list of its pros and cons from an end user perspective and go over how to set it up on Qubes OS. Advantages Provides anonymity by removing trust in a service provider (as opposed to a traditional VPN) Better versatility than Tor by supporting any IP based protocols (Tor only supports TCP) Generally faster speed than the Tor Network Disadvantages Only works well on Debian-based distributions....

July 27, 2022 · 4 min · 788 words · Tommy

Using Mullvad VPN on Qubes OS

Mullvad is a fairly popular and generally trustworthy VPN provider. In this post, I will walk you through how to use the official Mullvad client in a ProxyVM on Qubes OS. This method is a lot more convenient than the official guide from Mullvad (which recommends that you manually load in OpenVPN or Wireguard profiles) and will let you seamlessly switch between different location and network setups just as you would on a normal Linux installation....

September 3, 2022 · 3 min · 494 words · Tommy