diff -ur sextractor-2.19.5/src/catout.c sextractor-2.19.5.prep/src/catout.c
--- sextractor-2.19.5/src/catout.c	2013-09-12 14:35:37.000000000 +0200
+++ sextractor-2.19.5.prep/src/catout.c	2014-03-26 18:25:06.390874672 +0100
@@ -999,7 +999,7 @@
       break;
 
     case ASCII_SKYCAT:
-      fprintf(ascfile, skycattail);
+      fprintf(ascfile, "%s", skycattail);
       if (!prefs.pipe_flag)
         fclose(ascfile);
       break;
diff -ur sextractor-2.19.5/src/xml.c sextractor-2.19.5.prep/src/xml.c
--- sextractor-2.19.5/src/xml.c	2013-04-27 15:22:23.000000000 +0200
+++ sextractor-2.19.5.prep/src/xml.c	2014-03-26 18:29:36.122059320 +0100
@@ -696,7 +696,7 @@
 		name, ucd);
       break;
     case P_STRING:
-      sprintf(value, (char *)key[i].ptr);
+      sprintf(value, "%s", (char *)key[i].ptr);
       fprintf(file, "   <PARAM name=\"%s\" datatype=\"char\" arraysize=\"*\""
 	" ucd=\"%s\" value=\"%s\"/>\n",
 	name, ucd, *value? value: " ");
@@ -705,13 +705,13 @@
       n = *(key[i].nlistptr);
       if (n)
         {
-        sprintf(value, ((char **)key[i].ptr)[0]);
+        sprintf(value, "%s", ((char **)key[i].ptr)[0]);
         fprintf(file, "   <PARAM name=\"%s\" datatype=\"char\""
 		" arraysize=\"*\" ucd=\"%s\" value=\"%s",
 		name, ucd, *value? value: " ");
         for (j=1; j<n; j++)
           {
-          sprintf(value, ((char **)key[i].ptr)[j]);
+          sprintf(value, "%s", ((char **)key[i].ptr)[j]);
           fprintf(file, ",%s", *value? value: " ");
           }
         fprintf(file, "\"/>\n");
@@ -722,7 +722,7 @@
 		name, ucd);
       break;
     case P_KEY:
-      sprintf(value, key[i].keylist[*((int *)key[i].ptr)]);
+      sprintf(value, "%s", key[i].keylist[*((int *)key[i].ptr)]);
       fprintf(file, "   <PARAM name=\"%s\" datatype=\"char\" arraysize=\"*\""
 	" ucd=\"%s\" value=\"%s\"/>\n",
 	name, ucd, value);
@@ -731,13 +731,13 @@
       n = *(key[i].nlistptr);
       if (n)
         {
-        sprintf(value, key[i].keylist[((int *)key[i].ptr)[0]]);
+        sprintf(value, "%s", key[i].keylist[((int *)key[i].ptr)[0]]);
         fprintf(file, "   <PARAM name=\"%s\" datatype=\"char\""
 		" arraysize=\"*\" ucd=\"%s\" value=\"%s",
 		name, ucd, value);
         for (j=1; j<n; j++)
           {
-          sprintf(value, key[i].keylist[((int *)key[i].ptr)[j]]);
+          sprintf(value, "%s", key[i].keylist[((int *)key[i].ptr)[j]]);
           fprintf(file, ",%s", value);
           }
         fprintf(file, "\"/>\n");