drAFL - AFL + DynamoRIO = Fuzzing Binaries With No Source Code On Linux

Original AFL supports black-box coverage-guided fuzzing using QEMU mode. I highly recommend to try it first and if it doesn't work you can try this tool.

You need to specify DRRUN_PATH to point to drrun launcher and LIBCOV_PATH to point to libbinafl.so coverage library. You also need to switch off AFL's fork server (AFL_NO_FORKSRV=1) and probably AFL_SKIP_BIN_CHECK=1. See step 5 in the build section below for more details.
NOTE: Don't forget that you should use 64-bit DynamoRIO for 64-bit binaries and 32-bit DynamoRIO for 32-bit binaries, otherwise it will not work. To make sure that your target is running under DynamoRIO, you can run it using the following command:
drrun -- <path/to/your/app/> <app_args>

Instrumentation DLL
Instrumentation library is a modified version of winAFL's coverage library created by Ivan Fratric.


Step 1. Clone drAFL repo
git clone https://github.com/mxmssh/drAFL.git /home/max/drAFL
cd /home/max/drAFL

Step 2. Clone and build DynamoRIO
git clone https://github.com/DynamoRIO/dynamorio
mkdir build_dr
cd build_dr/
cmake ../dynamorio/
make -j
cd ..
If you have any problems with DynamoRIO compilation check this page

Step 3. Build coverage tool
mkdir build
cd build
cmake ../bin_cov/ -DDynamoRIO_DIR=../build_dr/cmake
make -j
cd ..

Step 4. Build patched AFL
cd afl/
cd ..

Step 5. Configure environment variables and run the target
cd build
mkdir in
mkdir out
echo "AAAA" > in/seed
export DRRUN_PATH=/home/max/drAFL/build_dr/bin64/drrun
export LIBCOV_PATH=/home/max/drAFL/build/libbinafl.so
../afl/afl-fuzz -m 500 -i in -o out -- ./afl_test @@
In case of afl_test you should expect 25-30 exec/sec and 1 unique crash in 2-3 minutes.

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