diff --git a/cham.h b/cham.h
index 0d0da501..b32c6cb8 100644
--- a/cham.h
+++ b/cham.h
@@ -23,7 +23,7 @@ NAMESPACE_BEGIN(CryptoPP)
 
 /// \brief CHAM block cipher information
 /// \since Crypto++ 7.1
-struct CHAM64_Info : public FixedBlockSize<8>, FixedKeyLength<16>
+struct CHAM64_Info : public FixedBlockSize<8>, public FixedKeyLength<16>
 {
     static const std::string StaticAlgorithmName()
     {
@@ -34,7 +34,7 @@ struct CHAM64_Info : public FixedBlockSize<8>, FixedKeyLength<16>
 
 /// \brief CHAM block cipher information
 /// \since Crypto++ 7.1
-struct CHAM128_Info : public FixedBlockSize<16>, VariableKeyLength<16,16,32,16>
+struct CHAM128_Info : public FixedBlockSize<16>, public VariableKeyLength<16,16,32,16>
 {
     static const std::string StaticAlgorithmName()
     {