diff --git a/src/trace/autotrace/inkscape-autotrace.cpp b/src/trace/autotrace/inkscape-autotrace.cpp
index b03223562f95dfea7cc80e34bd2ae4279266d7dd..3feea4c0bd9af6ffa38798e482cfef578c4724f8 100644
--- a/src/trace/autotrace/inkscape-autotrace.cpp
+++ b/src/trace/autotrace/inkscape-autotrace.cpp
@@ -145,7 +145,7 @@ std::vector<TracingEngineResult> AutotraceTracingEngine::trace(Glib::RefPtr<Gdk:
                 thePath.clear();
                 nNodes = 0;
             }
-            std::sprintf(color, "#%02x%02x%02x;", list.color.r, list.color.g, list.color.b);
+            std::snprintf(color, sizeof(color), "#%02x%02x%02x;", list.color.r, list.color.g, list.color.b);
 
             theStyle << ((spline.centerline || list.open) ? "stroke:" : "fill:") << color
                      << ((spline.centerline || list.open) ? "fill:" : "stroke:") << "none";
diff --git a/src/ui/svg-renderer.cpp b/src/ui/svg-renderer.cpp
index e8901d550a4780d9dd249f4f139ff8a5628306a4..ec07c88e9bb011c38fd4a6c0bbf2440c9a7b90ca 100644
--- a/src/ui/svg-renderer.cpp
+++ b/src/ui/svg-renderer.cpp
@@ -22,7 +22,7 @@ namespace Inkscape {
 
 Glib::ustring rgba_to_css_color(double r, double g, double b) {
     char buffer[16];
-    sprintf(buffer, "#%02x%02x%02x",
+    snprintf(buffer, sizeof(buffer), "#%02x%02x%02x",
         static_cast<int>(r * 0xff + 0.5),
         static_cast<int>(g * 0xff + 0.5),
         static_cast<int>(b * 0xff + 0.5)
@@ -43,7 +43,7 @@ Glib::ustring rgba_to_css_color(const SPColor& color) {
 Glib::ustring double_to_css_value(double value) {
     char buffer[32];
     // arbitrarily chosen precision
-    sprintf(buffer, "%.4f", value);
+    snprintf(buffer, sizeof(buffer), "%.4f", value);
     return Glib::ustring(buffer);
 }