zan00789/beebug

A tool for checking exploitability

beebug - A tool for checking exploitability

Description

beebug is a tool that can be used to verify if a program crash could be exploitable.

This tool was presented the first time at r2con 2018 in Barcelona.

Some implemented functionality are:

• Stack overflow on libc
• Crash on Program Counter
• Crash on branch
• Crash on write memory
• Heap vulnerabilities
• Read access violation (some exploitable cases)
• Help to analyze a crash (graph view)

Dependencies

• r2pipe
• pydot
• graphviz
• pyqtgraph

Installation

~ $ wget https://github.com/radare/radare2/archive/2.7.0.tar.gz
~ $ tar xzvf 2.7.0.tar.gz
~ $ cd radare2-2.7.0/
~/radare2-2.7.0 $ ./configure --prefix=/usr
~/radare2-2.7.0 $ make -j8
~/radare2-2.7.0 $ sudo make install
# apt-get install graphviz
# pip3 install -r requirements.txt

Usage

help

$ python3 ./beebug.py -h
usage: beebug.py [-h] [-t TARGET] [-a TARGETARGS] [-f FILE] [-g GRAPH] [-i]
                 [-r REPORT_FILE] [-v]

optional arguments:
  -h, --help            show this help message and exit
  -t TARGET, --target TARGET
                        target program to analyze
  -a TARGETARGS, --targetargs TARGETARGS
                        arguments for the target program
  -f FILE, --file FILE  input file
  -g GRAPH, --graph GRAPH
                        generate the graph
  -i, --instrumentation
                        instrumentation option
  -r REPORT_FILE, --report_file REPORT_FILE
                        DynamoRIO report file to parse

Simple usage

# python3 ./beebug.py -t tests/crash_on_pc
Process with PID 7691 started...
File dbg:///home/invictus1306/Documents/r2conf/beebug/beebug/tests/crash_on_pc  reopened in read-write mode
= attach 7691 7691
child stopped with signal 11
[+] SIGNAL 11 errno=0 addr=0x00601038 code=2 ret=0
Crash on PC - Generally it is exploitable, the PC could be tainted
backtrace
0  0x601038           sp: 0x0                 0    [??]  obj.foo obj.foo0
1  0x4004f1           sp: 0x7ffdfa75d8e8      0    [sym.main]  main+27 
2  0x7f2669d00830     sp: 0x7ffdfa75d908      32   [??]  r11+240 
3  0x7f266a0ba7cb     sp: 0x7ffdfa75d998      144  [??]  sym.dl_rtld_di_serinfo+29051 
4  0x400409           sp: 0x7ffdfa75d9c8      48   [??]  entry0+41
registers
rax = 0x00601038
rbx = 0x00000000
rcx = 0x00000000
rdx = 0x7ffdfa75d9f8
r8 = 0x00400570
r9 = 0x7f266a0baab0
r10 = 0x00000846
r11 = 0x7f2669d00740
r12 = 0x004003e0
r13 = 0x7ffdfa75d9e0
r14 = 0x00000000
r15 = 0x00000000
rsi = 0x7ffdfa75d9e8
rdi = 0x0000000a
rsp = 0x7ffdfa75d8e8
rbp = 0x7ffdfa75d900
rip = 0x00601038
rflags = 0x00010206
orax = 0xffffffffffffffff

Graph generation

# python3 ./beebug.py -t tests/crash_on_pc -g crash_on_pc
...
$ display crash_on_pc.png

Report parsing

Parse the report produced by functrace, and generate the graph.

Generate report using functrace

$ drrun -c libfunctrace.so -report_file report -disas_func main -cbr -- ./tests/reports/simple_test
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Run beebug for graph generation

$ python3 beebug.py -i -r ./tests/reports/report -g ./tests/reports/report

beebugreport

Future direction

• Support different architectures
• Improvement of the graph view (based on radare2)
• Analyze core dumps (based on radare2)
• Use instrumentation for the graph view generation

Lead Developer

• Andrea Sindoni - Twitter