diff --git a/third_party/libopenjpeg20/j2k.c b/third_party/libopenjpeg20/j2k.c
index d24564cc2..889c2cfc8 100644
--- a/third_party/libopenjpeg20/j2k.c
+++ b/third_party/libopenjpeg20/j2k.c
@@ -6397,7 +6397,7 @@ static OPJ_BOOL opj_j2k_add_mct(opj_tcp_t * p_tcp, opj_image_t * p_image,
     if (l_deco_array) {
         l_data_size = MCT_ELEMENT_SIZE[l_deco_array->m_element_type] * p_image->numcomps
                       * p_image->numcomps;
-        if (l_deco_array->m_data_size != l_data_size) {
+        if (l_deco_array->m_data_size != l_data_size || ! l_deco_array->m_data) {
             return OPJ_FALSE;
         }
 
@@ -6418,7 +6418,7 @@ static OPJ_BOOL opj_j2k_add_mct(opj_tcp_t * p_tcp, opj_image_t * p_image,
     if (l_offset_array) {
         l_data_size = MCT_ELEMENT_SIZE[l_offset_array->m_element_type] *
                       p_image->numcomps;
-        if (l_offset_array->m_data_size != l_data_size) {
+        if (l_offset_array->m_data_size != l_data_size || ! l_offset_array->m_data) {
             return OPJ_FALSE;
         }