diff --git a/infra/base-images/base-builder/compile_libfuzzer b/infra/base-images/base-builder/compile_libfuzzer
index d91945c53..3e553d350 100755
--- a/infra/base-images/base-builder/compile_libfuzzer
+++ b/infra/base-images/base-builder/compile_libfuzzer
@@ -18,7 +18,8 @@
 echo -n "Compiling libFuzzer to $LIB_FUZZING_ENGINE ..."
 mkdir -p $WORK/libfuzzer
 pushd $WORK/libfuzzer > /dev/null
-$CXX $CXXFLAGS -std=c++11 -O2 $SANITIZER_FLAGS -c $SRC/libfuzzer/*.cpp -I$SRC/libfuzzer
+$CXX $CXXFLAGS -std=c++11 -O2 $SANITIZER_FLAGS -fno-sanitize=vptr \
+    -c $SRC/libfuzzer/*.cpp -I$SRC/libfuzzer
 ar r $LIB_FUZZING_ENGINE $WORK/libfuzzer/*.o
 popd > /dev/null
 rm -rf $WORK/libfuzzer
diff --git a/projects/ffmpeg/build.sh b/projects/ffmpeg/build.sh
index 6e174a0bb..6890d261e 100755
--- a/projects/ffmpeg/build.sh
+++ b/projects/ffmpeg/build.sh
@@ -15,6 +15,10 @@
 #
 ################################################################################
 
+# Disable UBSan vptr since several targets built with -fno-rtti.
+export CFLAGS="$CFLAGS -fno-sanitize=vptr"
+export CXXFLAGS="$CXXFLAGS -fno-sanitize=vptr"
+
 # Build dependencies.
 export FFMPEG_DEPS_PATH=$SRC/ffmpeg_deps
 mkdir -p $FFMPEG_DEPS_PATH
diff --git a/projects/ffmpeg/project.yaml b/projects/ffmpeg/project.yaml
index c297dc543..dd7bc928b 100644
--- a/projects/ffmpeg/project.yaml
+++ b/projects/ffmpeg/project.yaml
@@ -2,5 +2,3 @@ homepage: "https://www.ffmpeg.org/"
 primary_contact: "ffmpeg-security@ffmpeg.org"
 auto_ccs:
  - "michaelni@gmx.at"
-sanitizers:
-- address