diff --git a/Zend/zend_hash.h b/Zend/zend_hash.h
index 2a640c174ec..6e73e49d070 100644
--- a/Zend/zend_hash.h
+++ b/Zend/zend_hash.h
@@ -330,6 +330,16 @@ static zend_always_inline zval *zend_hash_str_find_ind(const HashTable *ht, cons
 }
 
 
+static zend_always_inline int zend_hash_str_exists_ind(const HashTable *ht, const char *str, size_t len)
+{
+	zval *zv;
+
+	zv = zend_hash_str_find(ht, str, len);
+	return zv && (Z_TYPE_P(zv) != IS_INDIRECT ||
+			Z_TYPE_P(Z_INDIRECT_P(zv)) != IS_UNDEF);
+}
+
+
 static zend_always_inline zval *zend_symtable_update(HashTable *ht, zend_string *key, zval *pData)
 {
 	zend_ulong idx;
diff --git a/ext/standard/tests/filters/bug73586.phpt b/ext/standard/tests/filters/bug73586.phpt
new file mode 100644
index 00000000000..3cae4662bff
--- /dev/null
+++ b/ext/standard/tests/filters/bug73586.phpt
@@ -0,0 +1,45 @@
+--TEST--
+Bug #73586 (php_user_filter::$stream is not set to the stream the filter is working on).
+--FILE--
+<?php
+class append_filter extends php_user_filter {
+    public $stream;
+    function filter($in, $out, &$consumed, $closing) {
+        while ($bucket = stream_bucket_make_writeable($in)) {
+            $consumed += $bucket->datalen;
+            stream_bucket_append($out, $bucket);
+        }
+        if ($closing) {
+            $bucket = stream_bucket_new($this->stream, "FooBar\n");
+            stream_bucket_append($out, $bucket);
+        }
+        return PSFS_PASS_ON;
+    }
+}
+stream_filter_register("append", "append_filter");
+$fin = fopen(__FILE__, 'rb');
+stream_filter_append($fin, 'append', STREAM_FILTER_READ);
+stream_copy_to_stream($fin, STDOUT);
+?>
+--EXPECT--
+<?php
+class append_filter extends php_user_filter {
+    public $stream;
+    function filter($in, $out, &$consumed, $closing) {
+        while ($bucket = stream_bucket_make_writeable($in)) {
+            $consumed += $bucket->datalen;
+            stream_bucket_append($out, $bucket);
+        }
+        if ($closing) {
+            $bucket = stream_bucket_new($this->stream, "FooBar\n");
+            stream_bucket_append($out, $bucket);
+        }
+        return PSFS_PASS_ON;
+    }
+}
+stream_filter_register("append", "append_filter");
+$fin = fopen(__FILE__, 'rb');
+stream_filter_append($fin, 'append', STREAM_FILTER_READ);
+stream_copy_to_stream($fin, STDOUT);
+?>
+FooBar
diff --git a/ext/standard/user_filters.c b/ext/standard/user_filters.c
index d809fbbd91d..a2ca8cc7d78 100644
--- a/ext/standard/user_filters.c
+++ b/ext/standard/user_filters.c
@@ -175,7 +175,7 @@ php_stream_filter_status_t userfilter_filter(
 		return ret;
 	}
 
-	if (!zend_hash_str_exists(Z_OBJPROP_P(obj), "stream", sizeof("stream")-1)) {
+	if (!zend_hash_str_exists_ind(Z_OBJPROP_P(obj), "stream", sizeof("stream")-1)) {
 		zval tmp;
 
 		/* Give the userfilter class a hook back to the stream */