From 361ed689cc8e56fd125f9d0d6508e9eb303bdca6 Mon Sep 17 00:00:00 2001
From: Cristy <urban-warrior@imagemagick.org>
Date: Tue, 27 Mar 2018 20:39:27 -0400
Subject: [PATCH] https://github.com/ImageMagick/ImageMagick/issues/1009

---
 coders/webp.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/coders/webp.c b/coders/webp.c
index fffccd77e..22f662bae 100644
--- a/coders/webp.c
+++ b/coders/webp.c
@@ -181,6 +181,8 @@ static MagickBooleanType IsWEBPImageLossless(const unsigned char *stream,
   /*
     Read simple header.
   */
+  if (length <= VP8_CHUNK_INDEX)
+    return(MagickFalse);
   if (stream[VP8_CHUNK_INDEX] != EXTENDED_HEADER)
     return(stream[VP8_CHUNK_INDEX] == LOSSLESS_FLAG ? MagickTrue : MagickFalse);
   /*
-- 
2.40.0