diff --git a/libavfilter/vf_crop.c b/libavfilter/vf_crop.c
index d190d725cc..775c8ff856 100644
--- a/libavfilter/vf_crop.c
+++ b/libavfilter/vf_crop.c
@@ -305,6 +305,7 @@ static void end_frame(AVFilterLink *link)
     CropContext *crop = link->dst->priv;
 
     crop->var_values[N] += 1.0;
+    avfilter_unref_buffer(link->cur_buf);
     avfilter_end_frame(link->dst->outputs[0]);
 }