diff --git a/whitebox/crypto_utils/crypto_util.h b/whitebox/crypto_utils/crypto_util.h
index bd29bc9..2bf785a 100644
--- a/whitebox/crypto_utils/crypto_util.h
+++ b/whitebox/crypto_utils/crypto_util.h
@@ -12,6 +12,7 @@
 #ifndef WHITEBOX_CRYPTO_UTILS_CRYPTO_UTIL_H_
 #define WHITEBOX_CRYPTO_UTILS_CRYPTO_UTIL_H_
 
+#include <cstdint>
 #include <string>
 
 namespace widevine {