Ivan R Blog

OPSEC tips for the general public

It's always a good idea to properly configure your computer and smartphone, know how to securely communicate with others and how to read, write and share content while protecting your

Privacy

Is the Guatemalan government asking citizens for their location to show them ads?

On Tuesday March 24th 2020, the president of Guatemala Alejandro Giammattei announced that his government was releasing a mobile application named Alerta Guate. This application would have 3 main features:

Privacy

Advice for Targets of Mobile Spyware

After publishing a blog post on spouseware, I started receiving many interesting messages about people claiming they were targets of spying attempts. Some of them had doubts about their partners

iOS

Introducing security.plist

tl;dr It's like security.txt but for iOS applications. As probably you know by now, I spend a lot of my free time reverse engineering iOS applications. But when

Privacy

What checkm8 means for stalkerware on iOS

On Friday, September 27th 2019 many of us on the mobile security community were surprised with the news of a SecureROM vulnerability disclosed on Twitter by @axi0mX. axi0mX described it

Reverse Engineering

Decrypting iOS applications - iOS 12 Edition

As some of you may know, with the release of iOS 12.4 Apple accidentally reintroduced a vulnerability already patched on iOS 12.3. Shortly after this discovery, @Pwn20wnd released

Privacy

Analyzing iOS Stalkerware Applications

Stalkerware (a.k.a. Spouseware) applications are invasive applications that an individual installs on a target's device (usually their partner) to spy on them, snooping in as much data as

Reverse Engineering

Investigating some subscription scam iOS apps

For some reason Apple allows "subscription scam" apps on the App Store. These are apps that are free to download and then ask you to subscribe right on launch. It's

Cryptography

Created an "age" mobile client

A few days ago Filippo Valsorda twitted about a simple, secure and modern encryption tool that will hopefully substitute gpg. Filippo, along with Ben Cox, published a document detailing the

Android

Mobile App Sec Assemble

One of the reasons why I write blog posts about mobile app sec is for future me. I don't have a good memory so these posts help me refresh techniques

Mobile

Who's collecting analytics data from mobile apps?

I have the absolute pleasure and honour of being one of the beta testers of the GuardianApp. In an upcoming post I'll be explaining in more detail how it helps

iOS

Announcing my very own course: "Reverse Engineer iOS Applications" 📱

Big news! (or at least for me 😬) I've decided to create my own take on an online course to show beginner and intermediate researchers how to reverse engineer iOS applications.

How Facebook-Research app works

Last night I saw this tweet from Will Strafach: After reading that article I just needed to reverse this iOS app and see how it worked, this is what I've

iOS

Tips for Mobile Bug Bounty Hunting

My good friend Pete Yaworski encouraged me to join the bug bounty scene for a long time before I decided to jump in and start using my mobile app sec

Fix SSL Kill Switch2 not showing on Settings

If you landed on this blog post, it probably means you already know what SSL Kill Switch2 is. Therefore I'm not going to explain what it is, but if you

Racism and sexism are never funny

My blog is intended to be a hub of knowledge around Technology, Mobile & Web Application Security, Cryptography, Coding and Hacking. However, this is a very different post. This is

iOS

What do Pointer Authentication Codes mean for iOS jailbreaking?

Yesterday, Sep 12th, Apple announced their next generation of iPhones. The iPhone X [s], X [s] Max and X [r] are the new members of the iPhone family and "the

iOS

Reverse Engineering iOS Apps - iOS 11 Edition (Part 2)

This is the second part of the "Reverse Engineering iOS Apps - iOS 11 Edition" series. In the first part of the series we learned how to setup your phone

Development

Formatting phone numbers in Swift

A simple code snippet to format 10 digit phone numbers in Swift 4.0, instead of including a big library, just implement a delegate function and a formatting function: The

Saving your Github SSH Keys in a USB Drive

Github provides 2 main options for connecting (cloning, fetching, pulling, pushing) to repositories. HTTPS and SSH: HTTPS: This is the easiest way to clone a repo from Github. It needs no setup, the port 443 (https) is usually open on all networks and when

iOS

Reverse Engineering iOS Apps - iOS 11 Edition (Part 1)

Even though there are already many, many blog posts, tutorials and even youtube videos about "reverse engineering iOS apps", every time Apple releases a new iOS version the

iOS

Proxy iOS 11 applications’ traffic

A big part of understanding how mobile apps work is to identify the endpoints they hit on the server side and the data they send and receive. In order to

Android

Installing self-signed certificates on Android

One of the best trends these days is the shift to encrypted Internet traffic, aka Transport Layer Security or TLS, and mobile apps are not the exception, often when testing

iOS

Fix Cydia Impactor crypto-osx.cpp:97 error

If you upgraded to macOS Hight Sierra 10.13.x changes are Cydia Impactor is giving you this error when trying to install an app: The text reads: crypto-osx.cpp:97 The user name or passphrase you entered is not correct. But beyond that

Jailbreaking

Installing Dropbear SSH on iOS 10.3.3

In December last year, @thimstar and @S1guza released H3lix a semi-untether jailbreak for all 32-bit devices on iOS 10.0 to 10.3.3. This is amazing, it means devices