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, '\0',$subject); var_dump($x);
Output for 5.4.45, 5.5.29 - 5.5.35, 5.6.13 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
NULL
Output for 5.4.2 - 5.4.44, 5.5.24 - 5.5.28, 5.6.8 - 5.6.12

Process exited with code 139.

preferences:
201.34 ms | 402 KiB | 251 Q