3v4l.org

run code in 300+ PHP versions simultaneously
<?php $regex = '/(xyz\Kaa)/'; $subject = "aaaaxyzaabaa"; // Comment/uncomment below as wanted. // All 3 functions are vulnerable (note, other functions are affected as well) $x=preg_replace($regex, '',$subject); var_dump($x);
Output for 5.4.8 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.6 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
string(10) "aaaaxyzbaa"

preferences:
223.16 ms | 404 KiB | 249 Q