diff --git a/libavcodec/cbs_h2645.c b/libavcodec/cbs_h2645.c
index 9039e0f6f4..742857bd19 100644
--- a/libavcodec/cbs_h2645.c
+++ b/libavcodec/cbs_h2645.c
@@ -824,6 +824,7 @@ static int cbs_h264_read_nal_unit(CodedBitstreamContext *ctx,
             err = cbs_h264_read_sei(ctx, &gbc, sei);
             if (err < 0) {
                 cbs_h264_free_sei(sei);
+                av_free(sei);
                 return err;
             }