iOS Pentesting Series Part 3- The Ceasefire

Kishor balan
7 min readAug 19, 2023

Hola mates,

What’s crackin’? I’ve miraculously wrapped up the last installment of this series in record time. And oh, by the way, my trusty microphone decided to play hide and seek during the video recording. Not cool, right? :/

Time’s ticking away, so let’s dive right in. In this episode, we’re gonna tackle the following points:

1. JailBreak detection Bypass
i. Using Tweaks
ii. Using Publicly available frida scripts
iii.Using Using the default Jailbreak Bypass module that is available in Objection framework.
iv.Making our own frida script for bypassing JailBreak detection.

2. Setting up the Proxy and Bypassing SSL Pinning
i. Configuring the Proxy
ii. SSL Pinning Bypass using Tweaks
iii. SSL Pinning Bypasss Using Objection
iv. SSL Pinning Bypasss using Frida scripts

3. Intercepting Flutter iOS applications.

1. JailBreak detection Bypass.

Method — 1: Using Tweaks, Hope you have already installed the Jailbreak detection bypass tweaks that are mentioned in my Part-1 article.
Most of those tweaks can be seen in the device settings.

Let's try the Hestia Bypass

Enabling Hestia for the target application.

Few applications may misbehave or won’t bypass even if we are enabling Hestia for them. ummm..Well in those cases, we have other options available in Hestia application.

> From the Hestia settings, Enable the Obj-C checks Patches only.

This will work in most cases, otherwise feel free to try other tweaks as well.

Method: 2

Using the default Jailbreak Bypass module that is available in Objection framework

i) Connect the target Application and execute the command shown below

Method -3 : Blindly trying out the publicly available frida scripts for bypassing Jailbreak detection

Here i used a publicly available script that was published in codeshare.
Frida CodeShare

Method-4 : Making our custom Frida Scripts for bypassing jailbreak Detection.

No coding exp? Don’t worry same goes here too ..lol

i) Connect the target application with objection and search for the Jailbreak detection classes

ii) Now enumerate the available methods in our target class

iii) Look for the Blask sheep xD

Awww there he is..

iv) Now let's make a simple script for Intercepting our target class

vi) Aww dear Objection made that this easy ❤

vii) However, The entire script is not required for us except the following small part..

vii) Lets modify the code to see whats really happening with those target class method and save that code that as a JS file.

viii) Import the script in Objection and see what value returns when the jailbreak detection prompt appears

It looks like a boolean data type and its returns 1 if the device is jailbroken

lx) Now lets slightly modify the code for tampering the return value with 0

x) import the script again and see what happens when the jailbreak detection class gets loaded

As you can see in the picture, with our custom frida script, we were able to tamper the return value if isJailbroken class method during the runtime.,
As a result, The Jailbreak detection will be bypassed.

2. Setting up the Proxy and Bypassing SSL Pinning

i) Setting up proxy:

i. Fire up the BurpSuite and listen a port for all interface.

ii. Add the proxy details in the device wifi configuration

iii. Now go the device browser and hit “http://burp”
iv. Download the CA certificate

v. After downloading the certificate, Head to the device settings , there we can see “Profile Downloaded”

vi. Install the profile

vii. Now from the settings, Search for “Trusted cert”, Grant Full trust.

vii. Now we will be able to capture applications in which the SSL pinning is not enabled (Eg: Browser)

Ah, well, now it’s time for the true antagonist to make its grand entrance — SSL certificate pinning.

1. How we can identify the chances of SSL certificate pinning?

i. After Configuring the Proxy, Fire up the target application and play with it .
ii. The application may misbehave as it is getting messed up with our fake CA certificate (Burp)
iii. Take a look at the Burp dashboard and confirm this Error

iv. This confirms the SSL pinning.

Now What? Let’s try to get rid of them with some iOS tweaks:

• SSLBypass
• SSL kill Switch

i. SSL Kill Switch

i. After enabling the SSL Kill switch, Restart the target application and make traffics.

ii. SSLBypass

You can download the binary file from : SSLBypass/packages/com.evilpenguin.sslbypass_1.0–5+debug_iphoneos-arm.deb at main · evilpenguin/SSLBypass (github.com)

And install it manually.

“Thats it! And mostly, like other ‘innocent’ tweaks, the application won’t bother showing up anywhere noticeable. Instead, it will be working its magic behind the scenes, all hush-hush. it’ll casually bypass the target application’s SSL pinning. ;)

• Similar to Android, We can also try the Frida scripts for bypassing SSL pinning:

1. https://codeshare.frida.re/@federicodotta/ios13-pinning-bypass/
2. https://codeshare.frida.re/@snooze6/ios-pinning-disable/
3. https://codeshare.frida.re/@machoreverser/ios12-ssl-bypass/

We can run the codeshare scripts as below:

frida -U --codeshare <project_name> -f <target_app_package_name>

3. Intercepting Flutter iOS applications.

No Errors in the the Burp dashboard and can’t Intercept???

Well then, it seems I detect the distinct aroma of the Flutter framework within your application.

i. Rename the app.ipa to app.zip and look inside
ii. Find the ‘frameworks’ folder and get inside

See, just as I oh-so-wisely predicted, this turned out to be one heck of a Flutter app…

Hope you remember what we just did in cases of an Android flutter application ( https://medium.com/@kishorbalan/its-all-about-android-ssl-pinning-bypass-and-intercepting-proxy-unaware-applications-91689c0763d8)

“Reflutter!!, We remember you”

i. Waste no time, reflutter the IPA

Thats it! Go install the IPA and capture the stuff.

It appears that I am concluding my iOS Pentesting series today. I hope it serves as a helping hand for those who have recently stepped into iOS pentesting and might be feeling a bit stuck. However, it’s worth noting that this doesn’t mean I’m finished with iOS pentesting altogether. There’s still a wealth of iOS pentesting topics to explore. Stay tuned for more exciting content to come! 😄

Awww damn i wrote a lot today!!!

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