Building and Testing ClamAV with Fuzzing Sanitizers

Build & Reproduce Fuzz Reports using OSS-Fuzz Tools

Check out the google/oss-fuzz repository and the clamav repo side by side. .

Then inside the oss-fuzz directory, run:

python3 infra/ build_image clamav
python3 infra/ build_fuzzers --sanitizer address clamav ../clamav
python3 infra/ reproduce clamav clamav_scanmap_fuzzer /path/to/poc_file

Tip: You can substitute address argument in the second command that selects the Address Sanitizer (ASan) with memory or undefined to use the Memory Sanitizer (MSan) or the Undefined Behavior Sanitizer (UBSan).

See for more details.

Build & Test Fuzz Targets Sanitizers in CMake (v0.104 and newer)

Inside your clamav git clone, run:

mkdir build-fuzz && cd build-fuzz

export CC=`which clang` && \
    export CXX=`which clang++` && \
    export SANITIZER=address && \
    cmake .. -G Ninja \
        -D OPTIMIZE=OFF \
        -D CMAKE_BUILD_TYPE="Debug" \
        -D ENABLE_FUZZ=ON \
    && \

This will build the fuzz target executables in the build-fuzz/fuzz/ directory. You can run them just like a regular program, passing the file as input.


./fuzz/clamav_scanfile_fuzzer /path/to/poc_file

ClamAV with Address Sanitizer (ASAN) in Autotools (v0.103 and older)

Building ClamAV with ASAN support can be extremely useful in detecting memory corruption and memory leaks. To build with ASAN, use a ..\configure line like the following:

CFLAGS="-ggdb -O0 -fsanitize=address -fno-omit-frame-pointer" LDFLAGS="-fsanitize=address" CXXFLAGS="-ggdb -O0 -fsanitize=address -fno-omit-frame-pointer" OBJCFLAGS="-ggdb -O0 -fsanitize=address -fno-omit-frame-pointer" ../configure --prefix=`pwd`/../installed --enable-debug --enable-libjson --with-systemdsystemunitdir=no --enable-experimental --enable-clamdtop --enable-libjson --enable-xml --enable-pcre --disable-llvm