diff --git a/libdjvu/DjVuText.cpp b/libdjvu/DjVuText.cpp

index 60a4f39..b11df7b 100644

--- a/libdjvu/DjVuText.cpp

+++ b/libdjvu/DjVuText.cpp

@@ -345,7 +345,8 @@ DjVuTXT::decode(const GP<ByteStream> &gbs)

   int textsize = bs.read24();

   char *buffer = textUTF8.getbuf(textsize);

   int readsize = bs.read(buffer,textsize);

-  buffer[readsize] = 0;

+  if (buffer)

+    buffer[readsize] = 0;

   if (readsize < textsize)

     G_THROW( ERR_MSG("DjVuText.corrupt_chunk") );

   // Try reading zones