diff --git a/config/optimize b/config/optimize
index 042e290376..2bdedc671b 100644
--- a/config/optimize
+++ b/config/optimize
@@ -56,6 +56,11 @@ HOST_CXXFLAGS="$HOST_CFLAGS"
 HOST_LDFLAGS="-Wl,-rpath,$ROOT/$TOOLCHAIN/lib -L$ROOT/$TOOLCHAIN/lib"
 HOST_LIBDIR="$ROOT/$TOOLCHAIN/lib"
 
+# work around Ubuntu default C*FLAGS 
+# see https://wiki.ubuntu.com/ToolChain/CompilerFlags#A-Wformat_-Wformat-security
+HOST_CFLAGS="$HOST_CFLAGS -Wno-format-security"
+HOST_CXXFLAGS="$HOST_CXXFLAGS -Wno-format-security" 
+
 # add distro specific library dirs
   # ubuntu/debian specific "multiarch support"
     FAMILY_TRIPLET=$(echo $HOST_NAME | sed -e "s,$(uname -m),$(uname -i),")