diff --git a/ext/standard/string.c b/ext/standard/string.c
index 25580ba5e3d..f4efa6c5002 100644
--- a/ext/standard/string.c
+++ b/ext/standard/string.c
@@ -2429,8 +2429,13 @@ PHP_FUNCTION(stripos)
 	}
 
 	haystack_len = Z_UNILEN_P(haystack);
+
+	if (haystack_len == 0) {
+		RETURN_FALSE;
+	}
+
 	if (Z_TYPE_P(needle) == IS_UNICODE || Z_TYPE_P(needle) == IS_STRING) {
-		if (!Z_UNILEN_P(needle)) {
+		if (!Z_UNILEN_P(needle) || Z_UNILEN_P(needle) > haystack_len) {
 			RETURN_FALSE;
 		}
 		if (Z_TYPE_P(haystack) != Z_TYPE_P(needle)) {
diff --git a/ext/standard/tests/strings/stripos.phpt b/ext/standard/tests/strings/stripos.phpt
new file mode 100644
index 00000000000..ef0efe5b236
--- /dev/null
+++ b/ext/standard/tests/strings/stripos.phpt
@@ -0,0 +1,55 @@
+--TEST--
+stripos() function test
+--FILE--
+<?php
+	var_dump(stripos("test string", "TEST"));
+	var_dump(stripos("test string", "strIng"));
+	var_dump(stripos("test string", "stRin"));
+	var_dump(stripos("test string", "t S"));
+	var_dump(stripos("test string", "G"));
+	var_dump(stripos("te".chr(0)."st", chr(0)));
+	var_dump(stripos("tEst", "test"));
+	var_dump(stripos("teSt", "test"));
+	var_dump(stripos("", ""));
+	var_dump(stripos("a", ""));
+	var_dump(stripos("", "a"));
+	var_dump(stripos("a", " "));
+	var_dump(stripos("a", "a"));
+	var_dump(stripos("", 1));
+	var_dump(stripos("", false));
+	var_dump(stripos("", true));
+	var_dump(stripos("a", 1));
+	var_dump(stripos("a", false));
+	var_dump(stripos("a", true));
+	var_dump(stripos("1", 1));
+	var_dump(stripos("0", false));
+	var_dump(stripos("1", true));
+	var_dump(stripos("\\\\a", "\\a"));
+
+	echo "Done\n";
+?>
+--EXPECT--
+int(0)
+int(5)
+int(5)
+int(3)
+int(10)
+int(2)
+int(0)
+int(0)
+bool(false)
+bool(false)
+bool(false)
+bool(false)
+int(0)
+bool(false)
+bool(false)
+bool(false)
+bool(false)
+bool(false)
+bool(false)
+bool(false)
+bool(false)
+bool(false)
+int(1)
+Done