diff --git a/src/security/certificate-subject-description.hpp b/src/security/certificate-subject-description.hpp
index 054caf3..0e56dfa 100644
--- a/src/security/certificate-subject-description.hpp
+++ b/src/security/certificate-subject-description.hpp
@@ -41,6 +41,7 @@
 class CertificateSubjectDescription
 {
 public:
+  explicit
   CertificateSubjectDescription(CryptoPP::BufferedTransformation& in)
   {
     decode(in);