diff --git a/NEWS b/NEWS
index 5cf236fb2b7..4d2b9ba8c41 100644
--- a/NEWS
+++ b/NEWS
@@ -7,6 +7,8 @@ PHP                                                                        NEWS
     getClosure()). (Dmitry, Bob)
   . Fixed bug #70662 (Duplicate array key via undefined index error handler).
     (Nikita)
+  . Fixed buf #70681 (Segfault when binding $this of internal instance method
+    to null). (Nikita)
 
 - Mcrypt:
   . Fixed bug #70625 (mcrypt_encrypt() won't return data when no IV was
diff --git a/Zend/tests/bug70681.phpt b/Zend/tests/bug70681.phpt
new file mode 100644
index 00000000000..a99180b0ce5
--- /dev/null
+++ b/Zend/tests/bug70681.phpt
@@ -0,0 +1,11 @@
+--TEST--
+Bug #70681: Segfault when binding $this of internal instance method to null
+--FILE--
+<?php
+
+$c = (new ReflectionMethod('SplStack', 'count'))->getClosure(new SplStack);
+$c = $c->bindTo(null);
+
+?>
+--EXPECTF--
+Warning: Cannot unbind $this of internal method in %s on line %d
diff --git a/Zend/zend_closures.c b/Zend/zend_closures.c
index 4430e7b2506..6631193e135 100644
--- a/Zend/zend_closures.c
+++ b/Zend/zend_closures.c
@@ -173,6 +173,12 @@ ZEND_METHOD(Closure, bind)
 		zend_error(E_WARNING, "Cannot bind an instance to a static closure");
 	}
 
+	if (newthis == NULL && !(closure->func.common.fn_flags & ZEND_ACC_STATIC)
+			&& closure->func.type == ZEND_INTERNAL_FUNCTION) {
+		zend_error(E_WARNING, "Cannot unbind $this of internal method");
+		return;
+	}
+
 	if (scope_arg != NULL) { /* scope argument was given */
 		if (Z_TYPE_P(scope_arg) == IS_OBJECT) {
 			ce = Z_OBJCE_P(scope_arg);