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Static Analysis Tools



BinNavi is a binary analysis IDE that allows to inspect, navigate, edit and annotate control flow graphs and call graphs of disassembled code.
It relies on IDA Pro but fREedom project is an attempt to remove that dependency and build on top of Capstone instead.


Metasm is a cross-architecture assembler, disassembler, compiler, linker and debugger.
It has some advanced features such as live process manipulation, GCC/Microsoft Visual Studio-compatible preprocessor, automatic backtracking in the disassembler (similar to "slicing"), C headers shrinking, linux/windows/remote debugging API interface, a C compiler/decompiler, a gdb-server compatible debugger, and various advanced features. It is written in pure Ruby, with no dependency.
Intel IA32 (16/32/64bits), MIPS, PPC. Ongoing: ARM
MZ, PE/COFF (32 and 64 bits), ELF (32 and 64 bits), Mach-O (incomplete) and UniversalBinary

REC Studio

  • x86, x64
  • Windows, Linux, Mac OS X
  • HLA disassembler

Useful commands:

decompile /tmp/myprog.c

click on a function in the "Project" function list to HLA disass it


  • Intel (32 and 64bits), and ARM (ARMv6, ARMv7 and ARM64) processors
  • Mach-O binaries (Mac and iOS), PE32/32+/64 Windows binaries and ELF binaries
  • decompiler
  • debugger
  • patcher

Binary Ninja

  • US$ 99
  • Clients: Linux, Windows, Mac OSX
git clone --recurse


  • ARM, ARM64 (ARMv8), Mips, PowerPC, Sparc, SystemZ & Intel

Intel XED

X86 Encoder Decoder Software Library
Manual here


The reverse engineering framework


git repo synced with mercurial repo


Amoco is a python package dedicated to the (static) analysis of binaries
Very young but promising, seems easy to add an arch
With BBL symbolic execution


Miasm is a a free and open source (GPLv2) reverse engineering framework. Miasm aims at analyzing/modifying/generating binary programs. * opening/modifying/generating PE/ELF 32/64 le/be using Elfesteem

  • Assembling/Disassembling ia32/ppc/arm
  • Representing assembly semantic using intermediate language
  • Emulating using jit (dynamic code analysis, unpacking, ...)
  • Expression simplification for automatic de-obfuscation
  • ...


Medusa is a disassembler designed to be both modular and interactive. It runs on Windows and Linux

It actually can do more than static


(was called SmartDec)
Native code to C/C++ decompiler
x86 and x86-64 architectures, ELF and PE file formats
IDA Pro & standalone versions, for Windows
Standalone i86 Windows version runs fine under Wine


fcd is a LLVM-based native program decompiler. There is support for custom optimization passes written in Python, helping users defeat custom obfuscation schemes.


Reverse engineering tool for x86/ARM/MIPS. Generates indented pseudo-C with colored syntax code.

Misc Static


diStorm3 is really a decomposer, which means it takes an instruction and returns a binary structure which describes it rather than static text, this is great for advanced binary code analysis


PyPEELF is a multi-platform binary editor written in Python, wxPython and BOA Constructor. It allows you to manage binary data in PE32, PE32+ (x64) and ELF binary files.

PyPEELF uses pefile to manage PE32 and PE32+ files and pyelf to manage ELF files. Besides, it uses winappdbg and pydasm in some others features like Task Running Viewer and Disassembling files.

PyPEELF was designed for Reverse Engineers who want to edit or visualize binary file data in multi-platforms. That is why PyPEELF runs under Windows and Unix/BSD operating systems

Retargetable decompiler

Support ELF & PE for Intel x86, ARM, ARM+Thumb, MIPS, PIC32, and PowerPC architectures
Online decompilation service available!


Binwalk is a fast, easy to use tool for analyzing and extracting firmware images.


Portable Reverse Engineering Framework
On github

apt-get install qtbase5-dev ...


A static analysis tool for binaries.


A powerful hexadecimal editor

sudo apt-key adv --keyserver --recv-keys A04A6C4681484CF1
sudo apt-get install apt-transport-https
echo "deb [arch=amd64,i386] synalysis non-free" |sudo tee /etc/apt/sources.list.d/hexinator.list
sudo apt-get update
sudo apt-get install hexinator


A library for translating the semantics of native code to LLVM IR. McSema support translation of x86 machine code, including integer, floating point, and SSE instructions


Reverse engineering (x86 / elf) to pseudo-C


A Patch Analysis and Binary Diffing Tool



Online disassembler

Poor man's tools

File, -z to uncompress, -s to inspect non-files, e.g. /dev/sda1

file -k [-z] [-s] mybin 


strings [-n min_length] -a -e [s|S|b|l|B|L] mybin



  • Dalvik: bytecode, dex & VM instructions


A tool for converting Android’s .dex format to Java’s .class format
See also DeObfuscate jar with dex tool

./ myapp.apk

This returns a file myapp-dex2jar.jar
Then use Java decompilers: jad, jd-gui, cf below


Similar to dex2jar but newer and supposed to handle cases where dex2jar was failing


Dex to Java decompiler


smali/baksmali is an assembler/disassembler for the dex format used by dalvik, Android’s Java VM implementation


It is a tool for reverse engineering 3rd party, closed, binary Android apps. It can decode resources to nearly original form and rebuild them after making some modifications; it makes possible to debug smali code step by step. Also it makes working with app easier because of project-like files structure and automation of some repetitive tasks like building apk, etc.

apktool d myapp.apk

Apk Multi-Tool

Swiss knive (was Apk Manager)
Contains apktool, smali/baksmali etc
on Github for Linux release

  • 9 decompile apk / 1 select apk / 9 decompile apk


Small script to prepare a sed script to inject resource strings into jad, to ease reversing.
Update: inject resource names for other resources than strings, will still be more explanatory than 0x7f123456
To be used e.g. after apktool / Apk Multi-Tool decompilation

cat $DECOMPILED_DIR/res/values/public.xml|grep "type=.string"|\
    sed 's/.*name="\?//;s/" id="\?/ /;s/"\? \/>//'|\
    awk --non-decimal-data '{print $2, int($2), $1}'\
    > getstring-pub
cat $DECOMPILED_DIR/res/values/strings.xml|grep '<string'|\
    sed 's/.*name="\?//; s/"\?>/ /;s/<\/string>//;s/#/\\#/g'\
    > getstring-str
join -1 3 -2 1 --nocheck-order getstring-pub getstring-str|\
    sed 's/[^ ]\+ \([[:alnum:]]\+\) [[:alnum:]]\+ \(.*\)/s#\1#"\2"#/'\
    > getstring-sed
rm getstring-pub getstring-str
cat $DECOMPILED_DIR/res/values/public.xml|grep "type="|\
    grep -v "type=.string"|\
    sed 's/.*type="\(.*\)" name="\(.*\)" id="\(.*\)" \/>/s#\3#\1:\2#/'\
    >> getstring-sed


find $1 -name "*.jad" -exec sed -i -f getstring-sed {} \;


Soot is a Java bytecode analysis and transformation framework, now supporting Dalvik too.
Get soot.jar


java -jar soot.jar --help|less

#In case you don't have the right platform android.jar, you can force using another one, e.g.:
#FORCEJAR="-force-android-jar /path/to/android-sdk-linux_x86/platforms/android-17/android.jar"
java -jar soot.jar -allow-phantom-refs -android-jars /path/to/android-sdk-linux_x86/platforms -src-prec apk -process-dir $1 -output-format jimple $FORCEJAR

java -jar soot.jar -allow-phantom-refs -android-jars /path/to/android-sdk-linux_x86/platforms -src-prec jimple -process-dir sootOutput -output-format dex
mv sootOutput/classes.dex .


Example of reverse-engineering and modding APK with smali:

  • in APK-Multi-Tool-Linux working dir:
    • Drop myapp.apk in place-apk-here-for-modding/
    • ./ (and leave it always open in a separate window)
    • 9 decompile / 1 select myapp.apk / 9 decompile
    • ./getstrings
    • Copy apk to dex2jar working dir
    • Copy getstring-sed to jad working dir
  • in dex2jar working dir:
    • ./ myapp.apk
    • Copy myapp-dex2jar.jar to jad working dir (and/or jd-gui)
  • in jad working dir:
    • ./unjar myapp-dex2jar.jar
    • ./ myapp-dex2jar
    • Analyse .jad file and understand what to modify
  • in jd-gui working dir:
    • As alternative analysis can also be done with jd-gui directly on .jar file
  • in APK-Multi-Tool-Linux working dir:
    • In working/ find corresponding .smali file and modify it
    • (in windows) 13 compile/sign/install

Lim Electronics' APK Decompiler

A GUI wrapper for apktool.jar, dex2jar.bat and jad.exe on Windows.

Example 2

Example of reverse-engineering and modding APK with Soot / jimple

  • in APK-Multi-Tool-Linux working dir:
    • Drop myapp.apk in place-apk-here-for-modding/
    • ./ (and leave it always open in a separate window)
    • 1 extract apk
    • Copy apk to soot working dir
  • in soot working dir:
    • ./ myapp.apk
    • Analyse and modify sootoutput/*.jimple files
    • ./
    • Copy classes.dex to overwrite APK-Multi-Tool-Linux/out/classes.dex
  • in APK-Multi-Tool-Linux working dir (in windows)
    • 3 zip apk / 2 regular app
    • 4 sign app
    • adb install place-apk-here-for-modding/repackaged-signed.apk


Dalvik Retargeting, a tool for converting Android’s .dex format to Java’s .class format

Retargeted .class:

./dare -d output_dir -e myapp.apk

Optimized retargeted .class: (using Soot, slow!)

./dare -o -d output_dir -e myapp.apk

Decompiled optimized retargeted .class: (using Soot, very slow!)

./dare -c -d output_dir -e myapp.apk


The goal of this project is to help analysts and reverse engineers to visualize compiled Android packages and their corresponding DEX code. APKInspector provides both analysis functions and graphic features for the users to gain deep insight into the malicious apps
Still beta and inactive for a year.
GUI around other tools


Reverse engineering, Malware analysis of Android applications … and more !

Seems to be able to tackle also dynamically loaded code, native code, reflection code


Java .dex file format decompiler
Inactive since 2009


FlowDroid is a context-, flow-, field-, object-sensitive and lifecycle-aware static taint analysis tool for Android applications

Mobile Sandbox

Provides online static analysis of malware images.

JEB Decompiler

Commercial ($1000)
Decompile Android apps and obfuscated Dalvik bytecode as well as MIPS 32-bit


Lobotomy is an Android security toolkit that will automate different Android assessments and reverse engineering tasks. The goal of the Lobotomy toolkit is to provide a console environment, which would allow a user to load their target Android APK once, then have all the necessary tools without needing to exit that environment.
Lobotomy leverages and provides wrappers around other popular tools such as Androguard, apktool, Dex2Jar, Frida
Introduction part 1, part 2, more to come


Joint Advanced Defect Assessment framework for android applications (JAADS, original name JADE) is a tool written in Java and Scala with the power of Soot to provide both interprocedure and intraprocedure static analysis for android applications.

Misc Android Static

Online decompilation at (using dex2jar, jad, apktool, zip/unzip)

Simplify: Generic Android Deobfuscator



Java Decompiler
To use on a jar (from dex2jar):

if [ "$ODIR" == "$1" ]; then
    echo "Error: expecting a file ending with .jar"
    exit 1
7z x -o${ODIR} $1
for d in $(find ${ODIR}/com -type d); do
  echo Entering $d
  cd $d
  # Clean Android stuffs
  rm *\$*.class
  for c in *.class; do
    $JAD $c
    # Want to keep the .class or not?
    rm $c
  cd -
./unjar myapp-dex2jar.jar


Helps converting Java 1.4, Java 1.5 or later classes so JAD gives better results


Aligns java-files, which are decompiled by jad

java -jar JadHelper-0.0.1.jar

No much effect on jad from dex


JD-GUI is a standalone graphical utility that displays Java source codes of “.class” files


Helper to manual de-obfuscate obfuscated jars

  • rename class/packages in a jar
  • match a jarjar-ed & obfuscated jar with a known jar,to find the 'same' classes
  • bytecode dump(asm)
  • class dependency graph


Java Overall Editor is a complex editor and viewer for compiled java binaries (.class files)







man elf


readelf -a -g -t --dyn-syms -W mybin



objdump -C -g -F -x -T --special-syms mybin
objdump -d -l -r -R -S mybin
objdump -D -l -r -R -S mybin


nm -a -C -S -s --special-syms mybin


Shared library dependencies:

ldd -v mybin



A Python module to read and work with PE (Portable Executable) files, see usage examples

#!/usr/bin/env python
import sys, pefile
pe = pefile.PE(sys.argv[1])
open('out.txt', 'w').write(pe.dump_info())

Can run under Linux


Can run with Wine


Can run with Wine


A Scriptable In-memory and On-disk PE Parsing Utility

Resource Hacker

Can run with Wine

Dependency Walker

Can run with Wine


Can run with Wine

DLL Export Viewer

Can run with Wine
Under Wine, require absolute path to DLL so: click on gears, "load functions from the following DLL file", Browse

PEBrowse Pro

Can run with Wine

Explorer Suite

  • CFF Explorer: Allows also to modify a PE
  • Signature Explorer
  • PE Detective
  • Task Explorer (32 & 64)

PE Insider


Windows Object Explorer 64-bit


Portable Executable (PE) file viewer

BORG Disassembler

Static protections


upx -d myfile
  • Crinkler: some insane PE packing tool coming from the demoscene world.
  • midgetpack Midgetpack is a binary packer for ELF binaries. The curve25519 is the real advantage of midgetpack. In this mode, you do not provide any password or key. Instead, a key file is generated at packing time. This key file must be used every time you wish to use the binary. When you start the binary, it will give a challenge and expect a response.
  • android-unpacker


Source code


Dynamic Analysis Tools



Metasm has debugging capabilities too.

Intel PIN tools

  • Official page
  • Windows, Linux, Mac OS X, Android
  • x86-32, x86-64 (only Intel platforms obviously)
  • binary instrumentation

The best way to think about Pin is as a "just in time" (JIT) compiler. The input to this compiler is not bytecode, however, but a regular executable. Pin intercepts the execution of the first instruction of the executable and generates ("compiles") new code for the straight line code sequence starting at this instruction. It then transfers control to the generated sequence. The generated code sequence is almost identical to the original one, but Pin ensures that it regains control when a branch exits the sequence. After regaining control, Pin generates more code for the branch target and continues execution. Pin makes this efficient by keeping all of the generated code in memory so it can be reused and directly branching from one sequence to another. In JIT mode, the only code ever executed is the generated code. The original code is only used for reference. When generating code, Pin gives the user an opportunity to inject their own code (instrumentation).



Triton is a dynamic binary analysis (DBA) framework. It provides internal components like a Dynamic Symbolic Execution (DSE) engine, a Taint Engine, an intermediate representation based on SMT2-Lib of the x86 and x86-64 instructions set, SMT simplification passes, an SMT Solver Interface and, the last but not least, Python bindings.


Inject JavaScript to explore native apps on Windows, Mac, Linux, iOS and Android.

Awesome Frida

A curated list of awesome projects, libraries, and tools powered by Frida.


An automated framework for monitoring and tampering system API calls of native iOS and Android apps


DynamoRIO is a runtime code manipulation system that supports code transformations on any part of a program, while it executes. DynamoRIO exports an interface for building dynamic tools for a wide variety of uses: program analysis and understanding, profiling, instrumentation, optimization, translation, etc. Unlike many dynamic tool systems, DynamoRIO is not limited to insertion of callouts/trampolines and allows arbitrary modifications to application instructions via a powerful IA-32/AMD64 instruction manipulation library. DynamoRIO provides efficient, transparent, and comprehensive manipulation of unmodified applications running on stock operating systems (Windows or Linux) and commodity IA-32 and AMD64 hardware.

For ARM, see also DynamoRIO-ARM and (dead?) DynamoRIO-for-ARM


The BitBlaze infrastructure provides a component, called TEMU, for dynamic binary analysis. TEMU is built upon a whole-system emulator, QEMU, and provides the following functionality:

  • Dynamic taint analysis. TEMU is able to perform whole-system dynamic taint analysis. Marking certain information sources (e.g., keystrokes, network inputs, reads for certain memory locations, and function call outputs) as tainted, TEMU keeps track of the tainted information propagating in the system. This feature also provides a plug-in environment for dynamic symbolic execution, in which symbolic values are marked as tainted, and concrete values as untainted.
  • OS awareness. Information about OS-level abstractions like processes and files is important for many kinds of analysis. Using knowledge of the guest operating system (Windows XP or Linux), TEMU can determine what process and module is currently executing, what API calls have been invoked (with their arguments), and what disk locations belong to which files.
  • In-depth behavioral analysis. TEMU is able to understand how an analyzed binary interacts with the environment, such as what API calls are invoked, and what outstanding memory locations are accessed. By marking the inputs as tainted (i.e., symbolic), TEMU provides insights about how outputs are formulated from inputs.


QEMU Interactive Runtime Analyser to do dynamic analysis as well as IDA does static analysis
Write-up example: ezhp
QIRA src now at

Vdb/Vtrace / Vivisect

  • debugger, static analysis
  • Windows, Linux, Android
  • Intel, ARM

vtrace is a cross-platform process debugging API implemented in python, and vdb is a debugger which uses it
vivisect is a Python based static analysis and emulation framework

S2 Dynamic tracer and decompiler for gdb


Self-optimizing cross-platform code tracer based on dynamic recompilation, powered by Frida and Capstone


Avatar is an event-based arbitration framework that orchestrates the communication between an emulator and a target physical device. Avatar's goal is to enable complex dynamic analysis of embedded firmware in order to assist in a wide range of security-related activities including (but not limited to) reverse engineering, malware analysis, vulnerability discovery, vulnerability assessment, backtrace acquisition and root-cause analysis of known test cases.


ADBI: Binary Instrumentation Framework for Android

Slides here

Dynamic Dalvik Instrumentation Framework for Android

Slides here


DECAF(short for Dynamic Executable Code Analysis Framework) is a binary analysis platform based on QEMU. This is also the home of the DroidScope dynamic Android malware analysis platform. DroidScope is now an extension to DECAF
Slides here and article here


Android Application Sandbox


Realtime Privacy Monitoring on Smartphones


Java, Dalvik (see here and here)




Comprehensive security and attack framework for Android
Interacts with Dalvik VM and explore applications attack surface (activities, content providers, services, etc).
Can also be used remotely à la Metasploit with exploits & payloads


A Scriptable Debugger for Android's Dalvik Virtual Machine


Hooker is an opensource project for dynamic analysis of Android applications. This project provides various tools and applications that can be use to automaticaly intercept and modify any API calls made by a targeted application. It leverages Android Substrate framework to intercept these calls and aggregate all their contextual information (parameters, returned values, ...) in an elasticsearch database. A set of python scripts can be used to automatize the execution of an analysis in order to collect any API calls made by a set of applications.


Changes app_process binary and hooks into all system or applications
Many modules
See also XDA forum

Cydia Substrate

Similar to Xposed but not via replacement of system components.
Hooks into Dalvik and native code


Simple and easy to use library to intercept virtual-method calls under the Android ART runtime.

Misc Android Dynamic



A reverse engineering framework for iOS



A tool that lets you intercept methods, alter data and otherwise hack Java applications running on your computer.



ActionScript Bytecode instrumentation framework



Tracing library calls and system calls.
Getting a summary:

ltrace -f -S mybin 2>&1|grep '(.*)'|sed 's/(.*//'|sort|uniq -c

Getting more:

ltrace -f -i -S -n 4 -s 1024 mybin


Tracing inner execution flow as well

Lib preloading

#define _GNU_SOURCE

#include <dlfcn.h>
#include <sys/types.h>
#include <unistd.h>
#include <errno.h>
#include <stdio.h>
#include <time.h>

// Kill nanosleep()
int nanosleep(const struct timespec *req, struct timespec *rem){
    printf("\n==== In our own nanosleep(), I dunnah want sleep\n");
    return 0;

// Kill usleep()
int usleep(useconds_t usec){
    printf("\n==== In our own usleep(), I dunnah want sleep\n");
    return 0;

// Fix time()
time_t time(time_t *t){
    printf("\n==== In our own time(), will return 1380120175\n");
    return 1380120175;

// Fix srand()
void srand(unsigned int seed){
    printf("\n==== In our own srand(), will do srand(0)\n");
    void (*original_srand)(unsigned int seed);
    original_srand = dlsym(RTLD_NEXT, "srand");
    unsigned int myseed = 0;
    return (*original_srand)(myseed);

#if 0
// Kill rand()
int rand(void){
    printf("\n==== In our own rand(), will return 0\n");
    return 0;
// Intercept rand()
int rand(void){
    int (*original_rand)(void);
    original_rand = dlsym(RTLD_NEXT, "rand");
    int r = (*original_rand)();
    printf("\n==== In our own rand(), will return %04X\n", r);
    return r;
gcc -fPIC -shared -Wl,-soname,patch -o patch.c -ldl


a quick open/close/ioctl/read/write/free symbol hooker


  • x86-32, x86-64, ARM (since v0.52)


scanmem is a simple interactive debugging utility for linux, used to locate the address of a variable in an executing process. This can be used for the analysis or modification of a hostile process on a compromised machine, reverse engineering, or as a "pokefinder" to cheat at video games.

  • Linux/Android
  • with a GUI since v0.13: GameConqueror


Enable binary writing, here changing a conditional jump to unconditional jump:

gdb -write -silent --args mycode 1 2 3
(gdb) set {unsigned char}0x400123 = 0xeb
(gdb) disassemble 0x400123 0x400124
0x400123 jmp 0x...

or injecting NOPs:

(gdb) set {unsigned char}0x400123 = 0x90


Stephen Bradshaw ha swritten some extensions to have more useful gdb info when debugging stripped binaries, closer to what you get with OllyDbg. See:


  • Voltron is an unobtrusive debugger UI for hackers
  • SchemDBG is a backend agnostic debugger frontend that focuses on debugging binaries without access to the source code


The ERESI Reverse Engineering Software Interface is a multi-architecture binary analysis framework with a domain-specific language tailored to reverse engineering and program manipulation.


rr aspires to be your primary debugging tool, replacing — well, enhancing — gdb. You record a failure once, then debug the recording, deterministically, as many times as you want. The same execution is replayed every time.
rr also provides efficient reverse execution under gdb. Set breakpoints and data watchpoints and quickly reverse-execute to where they were hit.


angr is a framework for analyzing binaries. It focuses on both static and dynamic symbolic ("concolic") analysis, making it applicable to a variety of tasks.



Process Monitor

Process Explorer


Computes diff between two registry snapshots



PE32-only dynamic disassembler and debugger:
Version 1.1 is historically widespread, version 2.0 is re-written from scratch, still considered as beta by some.
Support software and hardware breakpoint, binary patching and repacking, symbol analysis, advanced instruction pattern search, trace with conditional breaking, etc.


There is also a patched version of OllyDbg with advanced python scripting ability called Immunity Debugger:
Expect some OllyDbg plugins to not work properly with ImmDbg.

  • Mona, a debugger plugin / Exploit Development Swiss Army Knife


The WinAppDbg python module allows developers to quickly code instrumentation scripts in Python under a Windows environment.

Based on WinAppDbg, finds interesting bits in trace by dichotomy signal/noise

  • run first time and try everything but not the interesting stuff -> use noise option
  • then run again and try interesting stuff -> use signal option

Find libraries loaded at runtime and the functions called


An open-source x64/x32 debugger for windows.

Visual DuxDebugger

Cuckoo Sandboxing

Currently only supporting Windows binaries.
Cuckoo Sandbox is a malware analysis system. You can throw any suspicious file at it and in a matter of seconds Cuckoo will provide you back some detailed results outlining what such file did when executed inside an isolated environment. Cuckoo generates a handful of different raw data which include:

  • Native functions and Windows API calls traces
  • Copies of files created and deleted from the filesystem
  • Dump of the memory of the selected process
  • Full memory dump of the analysis machine
  • Screenshots of the desktop during the execution of the malware analysis
  • Network dump generated by the machine used for the analysis


Unknown price







  • Ropper, rop gadget finder and binary information tool, based on Capstone
  • ROPgadget, supports ELF/PE/Mach-O format on x86, x64, ARM, PowerPC, SPARC and MIPS architectures
  • ROPshell, online, supports ELF/PE/Mach-O format on x86, x64, ARM
  • nROP, semantic ROP search, based on LLVM & Z3
  • pwntools
  • PEDA: Python Exploit Development Assistance for GDB (x86/x64)
  • GEF: GDB enhanced features - multi-arch (x86/x64/mips/ppc/arm)
  • Hexcellents notes
  • ROP on ARM (pdf) by Xipiter / dontstuffbeansupyournose
  • Framing Signals a return to portable shellcode: article, slides
  • BARF : A multiplatform open source Binary Analysis and Reverse engineering Framework

Mitigation techniques

Some are taken from excellent Android Hacker's Handbook

Hardening the Heap

Hardened version of dlmalloc? Alternatives?

This can be done with LD_PRELOAD, e.g. with tcmalloc


Protecting against Integer Overflows

  • Protected calloc?
  • Hardened library for safe integer operations: safe_iop

Preventing Data Execution

Set stack (and heap) as non-executable.
Kernel marks stack as executable unless it finds a GNU_STACK program header without executable flag set.
To insert non-exec statement:

flag: -znoexecstack

To test:

/usr/sbin/execstack -q myprog
  • "?": myprog has no GNU_STACK -> stack is executable
  • "-": stack non-executable
  • "X": stack executable


readelf -a myprog|grep -A1 GNU_STACK
  • present? with RW or RWE?


cat /proc/123/maps|grep -E '(stack|heap)'
  • rw or rwx?

To modify existing bin:

/usr/sbin/execstack -s myprog # set executable stack
/usr/sbin/execstack -c myprog # clear

Max nr of process IDs

/sbin/sysctl kernel.pid_max

Traditionally 32768

/sbin/sysctl -w kernel.pid_max=4194303


/sbin/sysctl kernel.yama.ptrace_scope

To allow ptrace:

/sbin/sysctl -w kernel.yama.ptrace_scope=0

Address Space Layout Randomization

Bin needs to be compiled position-independent:


To test:

readelf -h myprog | grep Type:
  • DYN? position-independent
  • EXEC? Not position-independent


readelf -d myprog | grep TEXTREL

Global settings

/sbin/sysctl kernel.randomize_va_space
/sbin/sysctl -w kernel.randomize_va_space=2
  • 0 – No randomization. Everything is static.
  • 1 – Conservative randomization. Shared libraries, stack, mmap(), VDSO and heap are randomized.
  • 2 – Full randomization. In addition to elements listed in the previous point, memory managed through brk() is also randomized.

To disable it locally (in a bash and its children)

setarch `uname -m` -R /bin/bash

On 32 bit systems “ulimit -s unlimited” disables the randomization of the mmap()-ing

Protecting the Stack

ProPolice stack protection is enabled by using

flags: -fstack-protector

Format String Protections

Enabled by using

flags: -Wformat-security -Werror=format-security

Beware compiler cannot detect all corner cases
See also _FORTIFY_SOURCE=2 for runtime protection against %n

Read-Only Relocations

Partial relro enabled by using

flags: -Wl,-z,relro

To test:

readelf -h myprog|grep RELRO
  • GNU_RELRO? Partial relro protection present

Full relro enabled by using

flags: -Wl,-z,relro -Wl,-z,now

To test:

readelf -d myprog|grep NOW
  • flags NOW? Full relro protection present

Access Control Mechanisms



Static source code analysis and fortifying


cppcheck --quiet --check-config .
cppcheck --xml --xml-version=2 --std=posix --std=c99 \
  --enable=style,performance,portability,information,unusedFunction \
  -I include --force --inconclusive .


flawfinder --quiet --dataonly --singleline --followdotdir .|sort -k 2 -r|less
flawfinder --immediate --dataonly --inputs --followdotdir .


export CFLAGS="-Wall -g -O2 -Wextra -pipe -funsigned-char -fstrict-aliasing -Wchar-subscripts -Wundef -Wshadow -Wcast-align -Wwrite-strings -Wunused -Wuninitialized -Wpointer-arith -Wredundant-decls -Winline -Wformat -Wformat-security -Wswitch-enum -Winit-self -Wmissing-include-dirs -Wmissing-prototypes -Wstrict-prototypes -Wold-style-definition -Wbad-function-cast -Wnested-externs -Wmissing-declarations "


export CFLAGS="-Wunreachable-code"
export CFLAGS="$CFLAGS -fno-omit-frame-pointer -D_FORTIFY_SOURCE=2 -fstack-protector"
export LDFLAGS="$LDFLAGS -fsanitizer=address -fno-omit-frame-pointer -D_FORTIFY_SOURCE=2 -fstack-protector"

Other resources







List of IR for reverse engineering

list collected by

Misc Resources

Going Maths