diff --git a/libwvdrmengine/cdm/util/src/string_conversions.cpp b/libwvdrmengine/cdm/util/src/string_conversions.cpp
index cd93dbbd..e40e6f7e 100644
--- a/libwvdrmengine/cdm/util/src/string_conversions.cpp
+++ b/libwvdrmengine/cdm/util/src/string_conversions.cpp
@@ -254,6 +254,8 @@ std::vector<uint8_t> Base64SafeDecode(const std::string& b64_input) {
 std::string HexEncode(const uint8_t* in_buffer, unsigned int size) {
   static const char kHexChars[] = "0123456789ABCDEF";
   if (size == 0) return "";
+  constexpr unsigned int kMaxSafeSize = 2048;
+  if (size > kMaxSafeSize) size = kMaxSafeSize;
   // Each input byte creates two output hex characters.
   std::string out_buffer(size * 2, '\0');