diff --git a/libavformat/mov.c b/libavformat/mov.c
index 2f6965eabb..f2eb22eb3d 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -3296,6 +3296,7 @@ static void mov_fix_index(MOVContext *mov, AVStream *st)
     // Free the old index and the old CTTS structures
     av_free(e_old);
     av_free(ctts_data_old);
+    av_freep(&frame_duration_buffer);
 
     // Null terminate the index ranges array
     current_index_range++;