3v4l.org

run code in 300+ PHP versions simultaneously
<?php $regex = '/((.a|aaa)|(?=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 - 5.5.38, 5.6.13 - 5.6.40, 7.0.0 - 7.0.33, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
NULL
Output for 5.4.0 - 5.4.44, 5.5.0 - 5.5.28, 5.6.0 - 5.6.12

Process exited with code 139.
preferences:
253.13 ms | 402 KiB | 372 Q