diff --git a/ssl/d1_both.c b/ssl/d1_both.c
index d1fc716d5..5d26c9492 100644
--- a/ssl/d1_both.c
+++ b/ssl/d1_both.c
@@ -1459,6 +1459,8 @@ int dtls1_process_heartbeat(SSL *s)
          * plus 2 bytes payload length, plus payload, plus padding
          */
         buffer = OPENSSL_malloc(write_length);
+        if (buffer == NULL)
+            return -1;
         bp = buffer;
 
         /* Enter response type, length and copy payload */
diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c
index 0e7a262a0..0bf0ea536 100644
--- a/ssl/t1_lib.c
+++ b/ssl/t1_lib.c
@@ -3858,6 +3858,8 @@ int tls1_process_heartbeat(SSL *s)
          * plus 2 bytes payload length, plus payload, plus padding
          */
         buffer = OPENSSL_malloc(1 + 2 + payload + padding);
+        if (buffer == NULL)
+            return -1;
         bp = buffer;
 
         /* Enter response type, length and copy payload */