diff --git a/imagespec.cpp b/imagespec.cpp
index 7fb0100..c412a79 100644
--- a/imagespec.cpp
+++ b/imagespec.cpp
@@ -258,7 +258,7 @@ void ImageSpec_set_channelformats(ImageSpec *spec, TypeDesc* formats){
 void ImageSpec_channelnames(ImageSpec *spec, char** out) {
 	std::vector<std::string> vec = static_cast<OIIO::ImageSpec*>(spec)->channelnames;
 	for (std::vector<std::string>::size_type i = 0; i != vec.size(); i++) {
-		out[i] = (char*)vec[i].c_str();
+		out[i] = strdup(vec[i].c_str());
 	}
 }
 
diff --git a/imagespec.go b/imagespec.go
index 1d66f40..7e6fb20 100644
--- a/imagespec.go
+++ b/imagespec.go
@@ -391,6 +391,7 @@ func (s *ImageSpec) ChannelNames() []string {
 	C.ImageSpec_channelnames(s.ptr, c_names_ptr)
 	for i, c := range c_names {
 		names[i] = C.GoString(c)
+		C.free(unsafe.Pointer(c))
 	}
 	runtime.KeepAlive(s)
 	return names