diff --git a/src/encoding/oid.cpp b/src/encoding/oid.cpp
index edbfa1a..f9085b2 100644
--- a/src/encoding/oid.cpp
+++ b/src/encoding/oid.cpp
@@ -17,6 +17,8 @@
 
 #include "../security/cryptopp.hpp"
 
+#include <sstream>
+
 using namespace std;
 using namespace CryptoPP;