Questions tagged [arm]
A family of instruction set architectures based on a RISC architecture developed by British company ARM Holdings. Heavily used in embedded devices such as mobile phones, tablets, set-top boxes, ...
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Address arithmetic in Ida Pro
Can someone tell more about address arithmetic in Ida? I were looking for assembly instructions and saw this
LDR R0, =(byte_255914C - 0xC63D50)
I understood right that in r0 will be an address which ...
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1
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73
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Cracking cryptographic function with radare2
I want to reverse engineer an android game, found a method
public static byte[] MNNOPKMJMFP(byte[] AFFEPNLBIIC, byte[] OENOGNMAMPO, byte[] GLLEHJKGIBK) { }
Names are obfuscated, i know that this is a ...
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Objective-C stub functions on AARCH64
I'm analyzing some functions I see in Machos binaries and I see that whenever there's bl instruction to an objective-c stub function that resides in the __objc_stubs section and in that function there'...
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What are some open source encoder-decoder libraries/binaries for ARM v8 and above?
A basic search yielded me results for Capstone disassembler for ARM v8, can I get details on some open source encoders and decoders for ARM v8 and above?
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How to pass an SVD file as an argument to IDA Pro in the command line (batch mode)?
I am trying to disassemble a few Arm Cortex-M3 .elf binaries and run a custom IDAPython script (script.py) from the command line (in batch mode). I have been able to do that with the following command:...
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103
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Why I can't decompile this ARM function?
I have an ARM (thumb) function from Nokia's firmware:
ROM:10A5409C srv_opps_normal_push_ind_handler ; CODE XREF: srv_opp_event_hdlr+1C6↑p
ROM:10A5409C
ROM:10A5409C var_18 = -0x18
ROM:...
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2
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101
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Determine Endianess of some ARM binary image?
I have been advised to analyze an ARM binary image from an Cortex M3 (STM32) for training. It has been directly extracted from flash beforehand and passed to me. However it's unknown whether this ...
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How to debug armel and armhf binaries on x86-64 Ubuntu simultaneously?
I'm working on the challenges on ROP Emporium. For the ARMv5 version of the callme challenge, we are given two binaries and two shared libraries: callme_armv5 with libcallme_armv5.so and callme_armv5-...
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JEB pro is not showing xrefs for native code (arm)
i have this problem when analyzing arm shared object.
when working with IDA pro, it finds all xrefs but in jeb, most of xrefs are missing.
when JEB finfishes, the final analysis lacks most of xrefs. I ...
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IDA Pro debugging an ARM binary on windows with QEMU
I have an arm executable which I was debugging with gdb-multi and qemu-arm on linux, how can I do the same with IDA pro on windows with QEMU, without needing a remote host for "remote debugging&...
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What is the best emulator/environment for android debugging?
I know the question smells like I want a ready solution but I have been trying many things and after a lot of headaches, still I can't do what I want.
There are fast emulators but they don't provide ...
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1
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137
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Identify mod operation in ARM firmware with IDA
I have the firmware in which mod operation must be done. I want to find this part of instructions.
Assume the following logic exist in the firmware:
res = var % 17
I have tried to make search by % ...
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218
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How to trace with Frida some specific functions in ARM ending with BX LR
I'am trying to trace down with Frida v16.0.11 (frida-trace) all calls to exported functions from "libssl.so" (Android, 32bit). But turns out that Frida is unable to hook some functions. One ...
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1
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Stuck decompiling ARM64 function
I am trying to figure out how this function squashes quaternion (double[4], dvar5..6 in the disassembly) data into the 2 int outputs vertexX and vertexY.
As far as I can tell, it reads the raw sensor ...
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How can I disassemble/decompile an immediate value to multiplication/summation of two values with IDA Pro?
Is it possible to force IDA to show "5 * 20" instead of "100" in the below disassembled and decompiled lines?
MOV R1, #100 -> MOV R1, #(5 * 20)
LDR R8, =var | ...
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💻 This code does not crash on ARM (qemu). Why?
I found a couple of interesting integer underflows leading to memcpy() wild copies in a TLV parser process of some random IoT firmware. It is 32-bit ARMv7.
I'm able to emulate the userspace process ...
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704
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Problem getting root shell on Ezviz camera
I got a CS-C6N Ezviz camera. My friend gave it to me because he doesn't use it anymore. I was able to get rtsp stream from the camera (but laggy), and I also was able to connect to UART port on the ...
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1
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156
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Understanding pointer indirection for accessing static variables in Cortex M0 firmware
I'm reverse engineering some firmware from a device running an ARM Cortex M0 (specifically, Nordic nrf51802). For reference, the pertinent part of the memory map looks like this:
I'm trying to add ...
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Using Hopper to flip branching instruction
Is it possible to flip branch instruction such as tbz to tbnz and b.ne to b.eq, I tried the hopper it gives syntax error
Is it possible to set a NOP on a bl or equivalent instruction using Hopper so ...
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1
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134
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Reversing C++ Classes in ARM
I have unstripped linux arm binary,
The code calls functions in class object reference like so:
LDR R3, [R6]
MOV R1, R7
MOV R0, R6
LDR R3, [R3,#0xC] ; (...
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394
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IDAPython set name of function using string passed to debug logging subfunction
IDA Pro 7.6
Static disassembly of ARM executable.
This binary has 40K functions or so, and no symbols. So all the functions are sub_49FFA etc.
However, 90% of these functions have a call to a debug ...
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269
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armv7 disassemble thumb instructions from raw binary snippet
I have a portion of a raw binary file that contains ARM instructions, specifically in Thumb mode (and I've manually disassembled a few instructions using the Architecture Manual, and they seemed ...
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1
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410
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How to get hexadecimal of instruction and distinct value(token) of opcode by ghidra script?
From disassembled code, I want to extract the hexadecimal of instruction, as boxed in the figure below
plus, I want to get distinct value of each opcode and its operand,
which means sort of
mov => ...
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5
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201
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Cannot find references to functions in vtables
First time doing RE work and I am working on a rather large C++ binary.
In Ghidra, there are many functions that do not appear to have any meaningful references to them (unlike some functions where ...
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ghidra assigns local variable to register
im reversing a android native library and im trying to understand how a token is generated the toke n is passed to a callback java method and i traced where the method is getting called from
this is ...
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56
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How can I quickly tell which ARM Thumb version a particular piece of code is using?
I'm working with an ARM processor: an STM32F407VGT6 board, which IIUC powers a 32-bit Arm® Cortex®-M4. I need to inspect the binary weight of some instruction, so I used objdump like this:
arm-none-...
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How to Decompile HP LaserJet Pro M12w firmware in Ghidra
I'm trying to decompile HP LaserJet Pro M12w firmware with Ghidra,
after download the HP LaserJet Firmware Update Utility from this link, when I look at this file, I found two file, hpm12a.pkg and ...
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1
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678
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U-boot base address on Ghidra
I'm trying to do some REing on a vendored U-Boot bootloader image.
For context, the U-Boot image was extracted from the full firmware image with:
dd if=<firmware>.img of=uboot_sdcard.bin bs=1024 ...
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2
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ARM (STM32) memory mapping on Ghidra: offset only part of the firmware file
I have a binary firmware that I'm trying to reverse engineer. I loaded it up on Ghidra, setting the file as raw binary, ARM Cortex, little endian. I used an address offset of zero for the file. And I ...
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Ghidra: Ignoring partial resolution of indirect
The decompiled code for a function shows "Warning: Ignoring partial resolution of indirect" and I am not able to determine the values of variables local_18 in this decompile:
uint ...
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1
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57
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Cutter cannot parse AUTDA instruction
I work on reverse engineering of an iOS software using Cutter, and receive several opcodes as "invalid". For example:
<addr> 301ac1da invalid
Looking up the hex ...
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2
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1
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578
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Trying to reverse a bin file
I'm trying to reverser a bin file with Ghidra, without success for the moment, I can't find any functions in the decompiled file.
he bin file is for an ARM 32bits, I'm pretty sure this is an stm32, so ...
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161
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Can an OpenWrt FIT kernel be virtualized in qemu?
I have a router I'd like to virtualize in order to do some dynamic analysis.
I could virtualize individual binaries with qemu, but I'd like to have the whole ecosystem up and running.
I'll start here:
...
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1
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79
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Is there any way to understand if a raw binary firmware is Cortex-M or not?
I have a list of firmwares, and I should filter just the Cortex-M type. Is there any automated way that I can distinguish them from other ARM firmwares?
I have some ideas like Interrupt vector Table (...
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1
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291
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Reverse engineering ELF: The e_phentsize field in the ELF header is less than the size of an ELF program header
I have extracted the .so binary libTheArmKing.so (located in lib directory in apk file) from a hack of World War Heroes game (an Android game) from Plantimod Forum.
file output:
libTheArmKing.so: ELF ...
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4
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3k
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Do I have to learn computer architecture for underestanding or doing reverse engineering?
I am completely noob in reverse engineering, and I've just started to learn it.
Now I have this question in my mind, that does a reverse engineer use any computer architecture knowledge for doing his/...
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772
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STM32 - Disable Voltage Check
I'm planning to edit the binary Firmware for an STM32F030K6T6 ARM microcontroller used in the IKEA Fyrtur blinds. In particular I'm trying to
disable the Voltage check (allow alternative power source)...
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70
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Patching a B(ranch) causes segfault in ARMv7 binary, while the same patch (with JMP) works on x64 binary
Any ideas why trying to patch a ARMv7 binary causes a segfault while basically the same patch on the Win64 version of the software works as expected?
Here is the Win64 version, that works
UPX0:...
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Gdb hardware watchpoint error on android
After failing to find a solution to this I have started using Gdb and have encountered another error.
Gdbfails to set hardware watchpoint when I'm remote debugging a rooted arm7-a target. It supports ...
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1k
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LLDB debugging on android?
I currently don't have a pc. I have two rooted devices Arm64 host device with Debian rootfs and the device to be debugged which contains the lldb-server binary armv7. I am trying to remote debug my ...
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What's the format of Mediatek MRE VXP file and how to create a workable VXP binary?
Background
Mediatek's MRE (MAUI Runtime Environment) is the default runtime on Nokia S30+ platform, replacing the J2ME platform on older Nokia. From MRE's page:
MRE (MAUI Runtime Environment) is a ...
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not called functions
trying to reverse a Cortex-M0 bin file using Ghidra.
There are functions that are Never Called any where in the code! (but actually should be called somewhere !)
What could be the reasons?
Tnx
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2
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178
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IDA show xrefs in .pdata and nothing else
I'm debugging the Windows ARM64 version's EFI (bootaa64.efi).
Using QEMU and GDB I was able to find that bootaa64.efi was stuck in one of the two functions BlKernelSp0SystemErrorHandler and ...
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745
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ARM - Understanding a "base address" when reversing firmware
I've read that when reversing firmware from an embedded system it's important to get the right base address of the firmware to make sure cross references to things such as strings work when looking at ...
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202
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Need help identifying this SoC
Does anybody know the manufacturer of this ARM CPU / SoC? I cannot find any information about it. I don't even know what the character in front of “Star” means.
“SAV500D” seems to be the model, the ...
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333
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Is it possible to dump firmware of a device via USB port?
I have a device which can be connected via USB port. The vendor of this device provides a tool for upgrading firmware of this device via USB port.
lsusb command says that this device has following ...
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1
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135
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ARM/THUMB assembly mismatch between binaries causes crash
I am trying to play around with an app for Android and every time I try to call a function (lua_gettop() from the Lua 5.1 library) from the app's address space, it hits me with ILL_ILLOPC.
I made sure ...
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673
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How to resolve illegal instruction for this ARM stack exploitation?
Summary
I am trying to write a stack overflow exploit for ARM Cortex-A72 running
Raspberry Pi OS (32-bit). Because of my choice of OS, I am restricted to
the ARMv7 (32-bit) instruction set.
I have ...
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1
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226
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ADDS(operations with S suffix) -Arm
This question was asked before here but in the answers I did get what i was looking for.
Consider this:
ADDS R0 RO R1
As far as I know to update the cpsr flags a subtraction has to be made. So after ...
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857
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android index.android.bundle file
I downloaded an app from Raccoon.
I got these files:
com.company.name-3423.apk
config.ar-3423.apk
config.armeabi_v7a-3423.apk
config.en-3423.apk
config.iw-3423.apk
config.ru-3423.apk
config.xhdpi-3423....
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