diff --git a/ngx_http_geoip2_module.c b/ngx_http_geoip2_module.c
index 0d76e34..d94bd42 100644
--- a/ngx_http_geoip2_module.c
+++ b/ngx_http_geoip2_module.c
@@ -226,12 +226,20 @@ ngx_http_geoip2_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v,
             FORMAT("%d", entry_data.boolean);
             break;
         case MMDB_DATA_TYPE_UTF8_STRING:
-            v->data = (u_char *) entry_data.utf8_string;
             v->len = entry_data.data_size;
+            v->data = ngx_pnalloc(r->pool, v->len);
+            if (v->data == NULL) {
+                return NGX_ERROR;
+            }
+            ngx_memcpy(v->data, (u_char *) entry_data.utf8_string, v->len);
             break;
         case MMDB_DATA_TYPE_BYTES:
-            v->data = (u_char *) entry_data.bytes;
             v->len = entry_data.data_size;
+            v->data = ngx_pnalloc(r->pool, v->len);
+            if (v->data == NULL) {
+                return NGX_ERROR;
+            }
+            ngx_memcpy(v->data, (u_char *) entry_data.bytes, v->len);
             break;
         case MMDB_DATA_TYPE_FLOAT:
             FORMAT("%.5f", entry_data.float_value);
diff --git a/ngx_stream_geoip2_module.c b/ngx_stream_geoip2_module.c
index dfd94ad..ad97ac6 100644
--- a/ngx_stream_geoip2_module.c
+++ b/ngx_stream_geoip2_module.c
@@ -195,12 +195,20 @@ ngx_stream_geoip2_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t
             FORMAT("%d", entry_data.boolean);
             break;
         case MMDB_DATA_TYPE_UTF8_STRING:
-            v->data = (u_char *) entry_data.utf8_string;
             v->len = entry_data.data_size;
+            v->data = ngx_pnalloc(r->pool, v->len);
+            if (v->data == NULL) {
+                return NGX_ERROR;
+            }
+            ngx_memcpy(v->data, (u_char *) entry_data.utf8_string, v->len);
             break;
         case MMDB_DATA_TYPE_BYTES:
-            v->data = (u_char *) entry_data.bytes;
             v->len = entry_data.data_size;
+            v->data = ngx_pnalloc(r->pool, v->len);
+            if (v->data == NULL) {
+                return NGX_ERROR;
+            }
+            ngx_memcpy(v->data, (u_char *) entry_data.bytes, v->len);
             break;
         case MMDB_DATA_TYPE_FLOAT:
             FORMAT("%.5f", entry_data.float_value);