1 files changed, 9 insertions, 0 deletions
diff --git a/libavcodec/wmv2dec.c b/libavcodec/wmv2dec.c
index 124dfdb7e0..afa65478e3 100644
--- a/libavcodec/wmv2dec.c
+++ b/libavcodec/wmv2dec.c
@@ -33,6 +33,7 @@
 static int parse_mb_skip(Wmv2Context *w)
 {
     int mb_x, mb_y;
+    int coded_mb_count = 0;
     MpegEncContext *const s = &w->s;
     uint32_t *const mb_type = s->current_picture_ptr->mb_type;
 
@@ -83,6 +84,14 @@ static int parse_mb_skip(Wmv2Context *w)
         }
         break;
     }
+
+    for (mb_y = 0; mb_y < s->mb_height; mb_y++)
+        for (mb_x = 0; mb_x < s->mb_width; mb_x++)
+            coded_mb_count += !IS_SKIP(mb_type[mb_y * s->mb_stride + mb_x]);
+
+    if (coded_mb_count > get_bits_left(&s->gb))
+        return AVERROR_INVALIDDATA;
+
     return 0;
 }