See: http://www.cups.org/str.php?L3914 for details.

Index: filter/image-gif.c

===================================================================

--- filter/image-gif.c	(revision 9862)

+++ filter/image-gif.c	(working copy)

@@ -648,11 +648,13 @@

     if (code == max_code)

     {

-      *sp++ = firstcode;

-      code  = oldcode;

+      if (sp < (stack + 8192))

+	*sp++ = firstcode;

+

+      code = oldcode;

     }

-    while (code >= clear_code)

+    while (code >= clear_code && sp < (stack + 8192))

     {

       *sp++ = table[1][code];

       if (code == table[0][code])

@@ -661,9 +663,11 @@

       code = table[0][code];

     }

-    *sp++ = firstcode = table[1][code];

-    code  = max_code;

+    if (sp < (stack + 8192))

+      *sp++ = firstcode = table[1][code];

+    code = max_code;

+

     if (code < 4096)

     {

       table[0][code] = oldcode;