diff --git a/ext/dom/characterdata.c b/ext/dom/characterdata.c
index b17679655bee1..6e47da166a364 100644
--- a/ext/dom/characterdata.c
+++ b/ext/dom/characterdata.c
@@ -104,7 +104,6 @@ Modern spec URL: https://dom.spec.whatwg.org/#dom-characterdata-substringdata
 PHP_METHOD(DOMCharacterData, substringData)
 {
 	zval *id;
-	xmlChar *cur;
 	xmlChar *substring;
 	xmlNodePtr node;
 	zend_long offset_input, count_input;
@@ -119,11 +118,7 @@ PHP_METHOD(DOMCharacterData, substringData)
 
 	DOM_GET_OBJ(node, id, xmlNodePtr, intern);
 
-	cur = node->content;
-	if (cur == NULL) {
-		/* TODO: is this even possible? */
-		cur = BAD_CAST "";
-	}
+	const xmlChar *cur = php_dom_get_content_or_empty(node);
 
 	length = xmlUTF8Strlen(cur);
 	if (ZEND_LONG_INT_OVFL(offset_input) || ZEND_LONG_INT_OVFL(count_input)) {
@@ -197,7 +192,7 @@ Modern spec URL: https://dom.spec.whatwg.org/#dom-characterdata-insertdata
 static void dom_character_data_insert_data(INTERNAL_FUNCTION_PARAMETERS, bool return_true)
 {
 	zval *id;
-	xmlChar		*cur, *first, *second;
+	xmlChar		*first, *second;
 	xmlNodePtr  node;
 	char		*arg;
 	zend_long        offset_input;
@@ -213,11 +208,7 @@ static void dom_character_data_insert_data(INTERNAL_FUNCTION_PARAMETERS, bool re
 
 	DOM_GET_OBJ(node, id, xmlNodePtr, intern);
 
-	cur = node->content;
-	if (cur == NULL) {
-		/* TODO: is this even possible? */
-		cur = BAD_CAST "";
-	}
+	const xmlChar *cur = php_dom_get_content_or_empty(node);
 
 	length = xmlUTF8Strlen(cur);
 
@@ -268,7 +259,7 @@ Modern spec URL: https://dom.spec.whatwg.org/#dom-characterdata-deletedata
 static void dom_character_data_delete_data(INTERNAL_FUNCTION_PARAMETERS, bool return_true)
 {
 	zval *id;
-	xmlChar    *cur, *substring, *second;
+	xmlChar    *substring, *second;
 	xmlNodePtr  node;
 	zend_long        offset, count_input;
 	unsigned int count;
@@ -282,11 +273,7 @@ static void dom_character_data_delete_data(INTERNAL_FUNCTION_PARAMETERS, bool re
 
 	DOM_GET_OBJ(node, id, xmlNodePtr, intern);
 
-	cur = node->content;
-	if (cur == NULL) {
-		/* TODO: is this even possible? */
-		cur = BAD_CAST "";
-	}
+	const xmlChar *cur = php_dom_get_content_or_empty(node);
 
 	length = xmlUTF8Strlen(cur);
 
@@ -340,7 +327,7 @@ Modern spec URL: https://dom.spec.whatwg.org/#dom-characterdata-replacedata
 static void dom_character_data_replace_data(INTERNAL_FUNCTION_PARAMETERS, bool return_true)
 {
 	zval *id;
-	xmlChar		*cur, *substring, *second = NULL;
+	xmlChar		*substring, *second = NULL;
 	xmlNodePtr  node;
 	char		*arg;
 	zend_long        offset, count_input;
@@ -356,11 +343,7 @@ static void dom_character_data_replace_data(INTERNAL_FUNCTION_PARAMETERS, bool r
 
 	DOM_GET_OBJ(node, id, xmlNodePtr, intern);
 
-	cur = node->content;
-	if (cur == NULL) {
-		/* TODO: is this even possible? */
-		cur = BAD_CAST "";
-	}
+	const xmlChar *cur = php_dom_get_content_or_empty(node);
 
 	length = xmlUTF8Strlen(cur);
 
diff --git a/ext/dom/php_dom.h b/ext/dom/php_dom.h
index 624e3cbaa5760..6d7c109c6eeb4 100644
--- a/ext/dom/php_dom.h
+++ b/ext/dom/php_dom.h
@@ -294,6 +294,11 @@ static zend_always_inline xmlNodePtr php_dom_first_child_of_container_node(xmlNo
 	}
 }
 
+static zend_always_inline const xmlChar *php_dom_get_content_or_empty(const xmlNode *node)
+{
+	return node->content ? node->content : BAD_CAST "";
+}
+
 PHP_MINIT_FUNCTION(dom);
 PHP_MSHUTDOWN_FUNCTION(dom);
 PHP_MINFO_FUNCTION(dom);
diff --git a/ext/dom/tests/null_text_content_manipulation.phpt b/ext/dom/tests/null_text_content_manipulation.phpt
new file mode 100644
index 0000000000000..9b1e35d60f766
--- /dev/null
+++ b/ext/dom/tests/null_text_content_manipulation.phpt
@@ -0,0 +1,33 @@
+--TEST--
+NULL text content manipulation
+--EXTENSIONS--
+dom
+--FILE--
+<?php
+$text = new DOMText();
+try {
+    var_dump($text->substringData(1, 0));
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+try {
+    var_dump($text->insertData(1, ""));
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+try {
+    var_dump($text->deleteData(1, 1));
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+try {
+    var_dump($text->replaceData(1, 1, ""));
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+?>
+--EXPECT--
+Index Size Error
+Index Size Error
+Index Size Error
+Index Size Error
diff --git a/ext/dom/text.c b/ext/dom/text.c
index ef0d5d0cef6f7..46b6f9d9dcc9d 100644
--- a/ext/dom/text.c
+++ b/ext/dom/text.c
@@ -100,7 +100,6 @@ Modern spec URL: https://dom.spec.whatwg.org/#dom-text-splittext
 PHP_METHOD(DOMText, splitText)
 {
 	zval       *id;
-	xmlChar    *cur;
 	xmlChar    *first;
 	xmlChar    *second;
 	xmlNodePtr  node;
@@ -120,11 +119,7 @@ PHP_METHOD(DOMText, splitText)
 		RETURN_THROWS();
 	}
 
-	cur = node->content;
-	if (cur == NULL) {
-		/* TODO: is this even possible? */
-		cur = BAD_CAST "";
-	}
+	const xmlChar *cur = php_dom_get_content_or_empty(node);
 	length = xmlUTF8Strlen(cur);
 
 	if (ZEND_LONG_INT_OVFL(offset) || (int)offset > length) {