Index: /trunk/src/VBox/Main/GuestImpl.cpp
===================================================================
--- /trunk/src/VBox/Main/GuestImpl.cpp	(revision 29511)
+++ /trunk/src/VBox/Main/GuestImpl.cpp	(revision 29512)
@@ -781,5 +781,10 @@
             AssertReturn(papszArgv, E_OUTOFMEMORY);
             for (unsigned i = 0; RT_SUCCESS(vrc) && i < uNumArgs; i++)
-                vrc = RTStrAPrintf(&papszArgv[i], "%s", Utf8Str(args[i]).raw());
+            {
+                int cbLen = RTStrAPrintf(&papszArgv[i], "%s", Utf8Str(args[i]).raw());
+                if (cbLen < 0)
+                    vrc = VERR_NO_MEMORY;
+
+            }
             papszArgv[uNumArgs] = NULL;
         }