diff --git a/NEWS b/NEWS
index bdc6ed53e..870287815 100644
--- a/NEWS
+++ b/NEWS
@@ -1,6 +1,8 @@
 ver 0.20.10 (not yet released)
 * decoder
   - ffmpeg: support MusicBrainz ID3v2 tags
+* tags
+  - aiff: fix FORM chunk size endianess (is big-endian)
 
 ver 0.20.9 (2017/06/04)
 * decoder
diff --git a/src/tag/Aiff.cxx b/src/tag/Aiff.cxx
index faa47f6b2..b6a7aa7ed 100644
--- a/src/tag/Aiff.cxx
+++ b/src/tag/Aiff.cxx
@@ -49,7 +49,7 @@ aiff_seek_id3(InputStream &is)
 	aiff_header header;
 	is.ReadFull(&header, sizeof(header));
 	if (memcmp(header.id, "FORM", 4) != 0 ||
-	    (is.KnownSize() && FromLE32(header.size) > is.GetSize()) ||
+	    (is.KnownSize() && FromBE32(header.size) > is.GetSize()) ||
 	    (memcmp(header.format, "AIFF", 4) != 0 &&
 	     memcmp(header.format, "AIFC", 4) != 0))
 		throw std::runtime_error("Not an AIFF file");