diff --git a/src/detector_network.cpp b/src/detector_network.cpp
index 6a9121ca..867e8ff2 100644
--- a/src/detector_network.cpp
+++ b/src/detector_network.cpp
@@ -69,7 +69,7 @@ DetectorNetwork::DetectorNetwork(
   std::unique_ptr<char> config_mutable(new char[config_file.size() + 1]);
   std::unique_ptr<char> weights_mutable(new char[weights_file.size() + 1]);
   snprintf(&*config_mutable, config_file.size() + 1, "%s", config_file.c_str());
-  snprintf(&*weights_mutable, config_file.size() + 1, "%s", weights_file.c_str());
+  snprintf(&*weights_mutable, weights_file.size() + 1, "%s", weights_file.c_str());
 
   const int clear = 0;
   impl_->network_ = load_network(&*config_mutable, &*weights_mutable, clear);