Questions tagged [ios]

The operating system by apple for mobile devices

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0answers
16 views

Backtrace HTTP request over few modules when using FRIDA

I am in the process of reverse engineering an IOS IPA using HOPPER and FRIDA. First, I started with POSTMAN, which records the app's HTTP requests. What I find interesting is that the app uses a so-...
4
votes
1answer
181 views

Reverse engineer compressed iOS app file

I want to find out the compression method used by an iOS app used for music notation to store its files. The files of its OSX counterpart are zipped files. You cannot create files in the iOS app, but ...
1
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0answers
60 views

How to get variable value during IDA (Hex-Rays Decompiler) debugging?

I'm debugging a iOS App by IDA, and I need to see the value of some var like v57 below. Through the Locals panel know the value is 0x1137D0E00LL, but I want to see the real value or class. How to get ...
62
votes
7answers
126k views

What are the possibilities for reverse engineering an IPA file to its source?

I browsed a lot, but can't find any resources for reverse engineering an IPA file (iPhone application). Is there any method to reverse engineer an IPA file to its source? I've tried to rename it to ...
0
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0answers
18 views

Change function implementation

I have a Mach-O 64-bit dynamically linked shared library (ARM64), wrote in Swift/Objective-C language for iOS. Is theoretically possible to open this file in Ghidra or IDA reverse tool, change some ...
0
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0answers
28 views

Is there any way to extract sandbox bundles since the implementation of monolithic kernelcaches?

I'm trying to obtain the same result that joker -K <bundle> <kernelcache> used to obtain. I tried using jtool2, but it appears that when I'm trying to extract a bundle nothing happens when ...
1
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1answer
52 views

Change iOS app binary file

I want to manipulate iOS binary file and change two strings in it. I used hex editor to search and change these strings. But after the binary file is uploaded and replaced with the origin app's binary ...
1
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0answers
78 views

Int64 parsing from args in Frida-trace for iOS binaries

I'm using frida-trace to log some methods and I've come across the following. onEnter(log, args, state) { log(`-[Somefunction somefield64:${args[2]}]`) } somefield64 returns what I believe to ...
1
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0answers
278 views

How are strokes stored in the Goodnotes file format?

I have been trying to reverse engineer the .goodnotes file format (a note taking app for iOS devices) and so far have discovered this: A .goodnotes file is simply a zip archive, an example file ...
5
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2answers
7k views

OTOOL alternative for linux

I have a reverse engineering set up on a Mac machine. This set up does some reverse engineering on iOS applications(.ipa files). I'm migrating the setup from Mac to a linux machine. Currently on Mac, ...
1
vote
1answer
287 views

Read and write to register with Frida

I have an instruction that looks like this in Ghidra: 100168ff0 e9 13 00 32 orr w9,wzr,#0x1f Using lldb I can set a breakpoint on the instruction after this, read w9 to confirm what ...
2
votes
2answers
477 views

Attempting to reverse engineer an iOS OTA payload-like archival format

Apple's announcement of macOS Big Sur had meant the release of the developer beta. In an attempt to create the appbundle from Apple's softwarecatalog, I attempted to study the contents of ...
0
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2answers
56 views

How to calculate the value needed to branch two points in IDA pro?

I need to find how to get the value to make a branch between two points in IDA Pro, but I can’t figure it out. For more context: the instructions I’m following says “Calculate the value needed to do a ...
0
votes
1answer
125 views

Why the disassembled code in IDA is different from in xcode? And How to solve unk_xxxx in IDA View?

I have built an executable file (the architecture is ARMv7, the base SDK is iOS), which depended on an xxx.a file in xcode; I don't have the source code of thexxx.a. I want to check some logic in `xx. ...
1
vote
1answer
113 views

Log input data and resulting hash for CC_MD5 calls in an iOS app with Frida

I am trying to understand the usage of calls to CC_MD5 in an iOS application. From Apple's man page I can see that when it is called it requires 3 arguments: extern unsigned char * CC_MD5(const void *...
0
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0answers
168 views

Stripped or not ? iOS App with unnamed symbol in LLDB

I am faced with an ambiguity being a novice. I'm trying to reverse an iOS application with LLDB and all the function coming from the app (native) are labeled as unnamed_symbol in the backtrace : The ...
2
votes
1answer
343 views

Ghidra : iOS Application : Mach-O binary -> Symbol files of dylib or framework are not generated

I'm performing my first reverse on a Mach-O file binary through Ghidra. My problem is that Ghidra doesn't create symbol files of the dylib/frameworks that are loaded in the project. It is really ...
2
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0answers
39 views

Attempting to understand non-XZ file signatures within PBZX chunks

After my previous question from nearly a year ago directing me to the YAA format to make sense of the chunks that could be decompressed, this time we're dealing with the chunks that made pbzx tell us ...
1
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0answers
53 views

How to find how a hash in generated in an iOS app

I'm currently working on an iOS app to replicate a signature which looks to be generated with a MD5 hash. I'm currently using Frida, but haven't had any luck replicating it. I've used the script to ...
2
votes
1answer
1k views

Setting Breakpoints at functions decoded by Hopper/IDA Pro in an iOS app

So, its been very interesting to reverse engineer an iOS application and I have made significant improvement into learning how to read disassembly and understand them. Now I was trying to debug the ...
1
vote
1answer
107 views

Radare2 - "/c pointer; offset" command not giving expected response to search instances of the same pair of similar instructions

I am trying to find an offset IOSURFACEROOTUSERCLIENT_VTAB from an iOS kext(IOSurface) using radare2 and there is a need to use the command "/c pointer; offset" as per the instructions in ...
0
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0answers
19 views

How to retrieve the function that has dispatched a message to the UI

I tried to reverse an iOS app, the purpose is to retrieve the moment when the application decides whether the activation was successful or not according to an HTTP response from the server. I'm trying ...
0
votes
0answers
56 views

How can i make more space for a bigger string in Hopper disassembler?

i made an ios app which simply change the background color when i tap the button. the goal is to change the color with hopper. I successfully changed the color from blue to red but i cannot change ...
1
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0answers
63 views

What kind of random algorithm is used in this game?

I am playing a game for iOS that uses a deck of 48 cards and I would like to reverse engineer the kind of algorithm that is used to generate the random deck of cards such that I can predict which card ...
0
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0answers
20 views

Reversing an iOS app for finding the SDKs installed

I tried decrypting the iOS Target retail app from AppStore for education purposes. The libraries / SDK's used in the app are very limited which is highly unlikely compared to other competitors in the ...
0
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0answers
29 views

Is it possible to somehow derive the decryption key for iOS app binaries?

While disassembling an IPA downloaded directly from the App Store CDN, I noticed that the binary had an unusually large entropy. Looking this occurrence up confirmed my suspicion that it was encrypted,...
0
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1answer
48 views

Dumping available XPC interface and methods

I'm reading this article, and it says: The following functions are exposed over XPC to the caller: @protocol _TtP4main21ForkLiftHelperProtcol_ - (void)changePermissions:(NSString *)arg1 permissions:(...
2
votes
1answer
156 views

Mysterious ARM instruction evaluating result to be 0xfe instead of 0xff

I'm facing some issues while debugging an iOS application for educational purposes. This is an iOS application found on the App Store and has some anti-debugging capabilities built in it. Pretext: ...
1
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0answers
43 views

finding specific string in ios dyld_shared_cache

Im trying to find the library inside a dyld cache that contains a specific string. I grepped the cache file and for the offset of the string, however when im throwing the cache file to ida non of the ...
11
votes
1answer
4k views

Generating Snapchat Snaptags ("QR" Codes)

For those that haven't seen, Snapchat now has a special type of image based code that allows you to quickly add friends by pointing the camera at the screen, similar to a QR code, called "Snaptags". ...
1
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0answers
42 views

Theos Tweak compilation errors [closed]

While attempting to build a Theos tweak, even a templated one created by Theos, I will encounter the following error bash: line 1: 4665 Done swift --version 4667 Broken pipe:...
11
votes
2answers
19k views

Decrypting IPA Binary on OS X

I've been reading this PDF on reverse-engineering iOS applications and have reached slide 39, decrypting the binary. However, I've been attempting to disassemble and explore the binary in OS X 10.9.5 ...
4
votes
3answers
7k views

Can not continue debugging after SIGTRAP

I am trying to debug an iOS app with gdb and when I hit a breakpoint I get this error, and can not continue. Program received signal SIGTRAP, Trace/breakpoint trap. [Switching to process 190 thread ...
1
vote
1answer
122 views

IDA - ObjC - Meaning of _BYTE and dword_0?

This is my first experience disassembling/reverse engineering, and am having a bit of difficulty keeping up. For reference, I'm trying to uncover the inner workings of a pretty good library in my ...
1
vote
1answer
60 views

Mach-O ARM64 using literal values instead of a frame pointer (BP) register

I'm investigating an iOS app Mach-O binary in IDA and noticed it's using a fixed constant as an offset to the SP to denote the start of the stack frame instead of a register. Is this normal? ARM ...
6
votes
1answer
453 views

How does IPA decryption works?

All IPAs being downloaded from AppStore gets encrypted on servers as part of FairPlay DRM. But decryption is accomplished on local device. As far as I know there is some hardware module which contains ...
1
vote
1answer
2k views

Using IDA Pro, How can I just "edit" values, Rather than patching Offsets,

Im a part of the iOSGods community, and they make lots of cheats, but they dont really do the best at teching other people how to do that. Those people never reply to my help support topics on ...
3
votes
0answers
532 views

Is there an existing tool to reverse engineer Xamarin AOTDATA files?

I am currently examining a xamarin application. It has used the "ahead of time compilation" feature, which has left some of the associated .net assemblies (.dlls) as lists of function signatures ...
1
vote
1answer
551 views

How to identify which iOS kernelcache is installed?

I've an iPhone7 running iOS11.3 (15E216). The ipsw for this build version contains two separate kernelcache files named kernelcache.release.iphone9 and kernelcache.release.iphone10. Neither file is an ...
3
votes
1answer
1k views

Lipo alternate for linux

Currently, I'm using lipo tool to extract the arch type from a fat iOS binary on a Mac OS. Now, I want to do the same on the linux platform for the iOS binaries, i.e. extract a given arch type from a ...
-1
votes
1answer
5k views

how should i change an instruction to NOP in IDA?

I am new with IDA assembler and i used to work with hopper app. the problem is i can't change instruction in IDA from something like CBNZ to NOP. is there any button to do this? i can't find anything ...
9
votes
2answers
7k views

How difficult is to decompile C++ file?

I am writing an Android app with AES encryption and I am going to save AES key as a string to a C++ file with extension .cpp. I am also going to create an iOS app which will use the same AES key. Is ...
3
votes
1answer
2k views

How does Apple enforce the expiration of beta apps distributed through TestFlight

A beta app expired after a period of time. But after some investigated on the ipa file, both the certificate and the mobile provisioning profile embedded in the bundle are not expired. How can Apple ...
42
votes
1answer
91k views

Decompiling iPhone App

I've been searching this site and more, but I haven't had much luck. I want to decompile an app to see how part of it works, and I've tried multiple programs. I've tried Hopper, IDA, and some other ...
0
votes
1answer
140 views

Accidently removed cordova platform ios folder [duplicate]

I was trying to uninstall a plugin but accidently ran the command cordova platform remove ios and it removed the app code on my macbook. I don't see anything in trash as well. Is there any way to ...
0
votes
1answer
216 views

Newbie here: hidden values in assembly? [closed]

So i'm new to the whole reverse engineering thing with only experience in C#. So I wanted to try and change the framerate of applications (eg. this unity game) at an assembly level on iOS ( I have an ...
2
votes
0answers
222 views

(iOS lldb) Unable to debug past a splash/loading screen

I'm trying to lldb debug this certain iOS application. Its behavior is that when I click the application, the splash/loading screen comes up, then the main activity. However, whenever I try to debug ...
1
vote
0answers
587 views

Patching an ipa (iPhone app) using Hopper Disassembler

I have learned in the past to patch some iOS apps to bypass jailbreak detection. Today, I decided to change the UI elements in the Spotify app on iOS Platform (ios 11). I downloaded a .ipa file of ...
4
votes
0answers
243 views

running iOS debugserver on non-jailbroken devices

There are multiple tutorials on how to debug applications on jailbroken devices. These usually involves resigning debugserver, scp and running it from ssh with few tweaks to the entitlements and ...
1
vote
1answer
1k views

iOS entitlements for enable calling to private API

I'd like to analyze iOS private framework that broke commonly used GitHub project called AppLister. Here's some info about the API: Framework : MobileCoreServices.framework. Class: ...