Questions tagged [angr]
angr is a Python binary analysis framework developed by the Computer Security Lab at UC Santa Barbara and their associated CTF team, Shellphish. project URL: https://github.com/angr/angr
25
questions
0
votes
0answers
28 views
Angr fails with unsat result even though there clearly exists a solution
recently I have been trying to solve the nobranch7e4 challenge from the HXP CTF 2020 using angr.
My success has been mixed: Even though there is no apparent state explosion I still cannot solve for ...
0
votes
0answers
28 views
What are the open source symbolic execution tools for Firmware?
I have tried to use angr, KLEE, S2E to symbolically analyze firmware binaries such as DIR-815(httpd ELF binary).
import claripy
import angr
p = angr.Project('./httpd', load_options={'auto_load_libs':...
1
vote
1answer
49 views
Using angr/radare2 to estimate values given chunks of assembly
I'm currently using radare2 in order to construct a simple CFG, each block/node in that graph is composed of one or more assembly instructions, I wish to estimate the value of specific register or ...
1
vote
1answer
77 views
Basic `angr` framework question- is something wrong with my solver?
I'm new to reverse engineering and I've just recently learned about angr, a framework that uses symbolic execution to get the input for a given output. I'm trying to complete a crackme using angr. My ...
1
vote
1answer
81 views
How to restrict angr to printable characters
I have a binary that scanfs and then does some checks and returns either FAIL or SUCCESS that has SUCCESS for multiple inputs. Although only one of the inputs has only printable characters. How do I ...
2
votes
0answers
61 views
Reverse engineering a command line argument using angr for an aarch64 binary
I am trying to reverse engineer a aarch64 binary using angr to find the required command line argument to get a desired result. From the binary I am able to extract the required length of the argument....
1
vote
2answers
180 views
Simple angr example not working
I am trying to learn angr from beginning. Due to lack of simple tutorials I programmed my own little executable which angr should solve.
The C code looks as follows:
#include <stdio.h>
#...
1
vote
1answer
378 views
How to export disassembly using angr
I would like to know how to export angr's disassembly in say txt file.
I looked at the angr documentation - https://angr.io/api-doc/angr.html#module-angr.analyses
I found that there are some ...
1
vote
0answers
59 views
Angr Use argv as initialstate
I am currently trying to use angr, and I need to find a string "Done!" which results in the "good termination" of the program. The input is 32 bits and I need to know the input which leads to the "...
4
votes
3answers
158 views
Get certain instruction count for multi-architecture binaries
I need to get an ELF binary's total count of
Function call instruction
conditional jump (branch) instruction
The binary could be any CPU architecture, like x64, ARM, MIPS, Motorola 68K, etc.
It ...
3
votes
0answers
313 views
Using Angr in Vulnerability Research
I would like to use angr for vulnerability research.
I was thinking that if I did the following:
p = angr.Project('a.out', auto_load_libs=False)
sm = p.factory.simulation_manager()
while len(sm....
2
votes
1answer
949 views
angr | populate int array with constraints
How do I populate memory address using angr with array of integers (?) and add a constraint so each int will be positive & less than 17 ?
I hope it's clear I need to find out the in_array ...
3
votes
0answers
278 views
How to prevent angr from taking dozens of hours and GB of memory solving a (seemingly) simple CTF problem
I was recently working on a (seemingly) simple CTF challenge where the input was a base64 encoded file and the binary would check for correctness in one function call. The catch is that the checking ...
4
votes
2answers
795 views
Angr - Solve for function return value
I'm trying to create an angr script to solve this test program:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(int argc, char *argv[])
{
int value = atoi(...
0
votes
2answers
702 views
Solve an angr function with string parameters
Look at this C code:
#include <stdio.h>
#include <string.h>
int my_function(char *s);
int my_function(char *s)
{
for (int i=0;i<strlen(s);i++)
{
s[i]++;
}
if (...
1
vote
1answer
333 views
Solve a function with angr [closed]
Look at this c program:
#include <stdio.h>
int my_function(int a, int b);
int my_function(int a, int b)
{
// Imagine a very complex calculation on 'a' and 'b'
if (a==0x41 && b=...
1
vote
1answer
265 views
Start Symbolic Analysis at a Given Address with Angr
Lets suppose I have a very big binary and I want to reverse just a part of this binary.
Is there a way to tell angr to start symbolic analysis at a given address ?
2
votes
1answer
261 views
angr with a golang target
Here is a very basic golang program:
package main
import "fmt"
func main() {
var s1 string
fmt.Scanln(&s1)
if s1=="goodpassword" {
fmt.Println("Good")
} else {
...
1
vote
1answer
422 views
Angr never finishes
I create the following c program as a proof of concept. When I try to analyze it with anger it never finishes.
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
char *...
4
votes
0answers
509 views
How do I perform concolic execution with Angr and collect constraints on input?
I have a program that takes a string (with some structure) as input. My aim is to collect information on what values each character in input is compared to as it gets parsed using concolic execution. ...
3
votes
1answer
159 views
angr multiple reads same variable
I'm writing a script to solve a binary that asks for multiple strings like the following c code,
My problem I can't dump the 'second_pass, I just get "first_pass".
probably due of the use of the same ...
2
votes
1answer
909 views
problem with scanf/fgets in angr stdin exploration
I want to solve this very basic crackme using angr:
#include <stdio.h>
#include <string.h>
int main(int argc, char *argv[]) {
char buffer[64];
printf("Mot de passe:\n");
...
0
votes
0answers
271 views
debugger trap with angr
Let's suppose this (very ugly) c code:
#include <stdio.h>
#include <string.h>
#include <signal.h>
char sav_argv[100];
void on_sigtrap(int signo)
{
if (strcmp(sav_argv, "hello")...
2
votes
2answers
955 views
Password Bruteforce using angr
I am having a binary which takes an input from user and checks every bit of our character using the check_value function which does some stuff. The disassembly of the interested function is:
.text:...
5
votes
1answer
699 views
How can I get the shared libraries' function calls using angr
I am trying to get all the library function calls that a binary performs in a preorder-DFT traversal of the CFG. I'm able to get the CFG like:
import sys, angr
import networkx as nx
proj = angr....
