diff --git a/src/Messaging/MessageBuffer.php b/src/Messaging/MessageBuffer.php
index e5d197b..5d6f82b 100644
--- a/src/Messaging/MessageBuffer.php
+++ b/src/Messaging/MessageBuffer.php
@@ -158,9 +158,19 @@ class MessageBuffer {
                 $payloadLenBytes = $payload_length === 126 ? 2 : 8;
                 $headerSize      += $payloadLenBytes;
                 $bytesToUpack    = substr($data, $frameStart + 2, $payloadLenBytes);
-                $payload_length  = $payload_length === 126
-                    ? unpack('n', $bytesToUpack)[1]
-                    : unpack('J', $bytesToUpack)[1];
+                $payloadLenOver2GB = false;
+
+                if ($payload_length === 126){
+                    $payload_length = unpack('n', $bytesToUpack)[1];
+                } else {
+                    $payloadLenOver2GB = unpack('N', $bytesToUpack)[1] > 0; //Decode only the 4 first bytes
+                    if (PHP_INT_SIZE == 4) { // if 32bits PHP
+                        $bytesToUpack = substr($bytesToUpack, 4); //Keep only 4 last bytes
+                        $payload_length = unpack('N', $bytesToUpack)[1];
+                    } else {
+                        $payload_length = unpack('J', $bytesToUpack)[1];
+                    }
+                }
             }
 
             $closeFrame = null;
@@ -170,6 +180,10 @@ class MessageBuffer {
                 $closeFrame = $this->newCloseFrame(Frame::CLOSE_PROTOCOL, 'Invalid frame length');
             }
 
+            if (!$closeFrame && PHP_INT_SIZE == 4 && $payloadLenOver2GB) {
+                $closeFrame = $this->newCloseFrame(Frame::CLOSE_TOO_BIG, 'Frame over 2GB can\'t be handled on 32bits PHP');
+            }
+
             if (!$closeFrame && $this->maxFramePayloadSize > 1 && $payload_length > $this->maxFramePayloadSize) {
                 $closeFrame = $this->newCloseFrame(Frame::CLOSE_TOO_BIG, 'Maximum frame size exceeded');
             }