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run code in 300+ PHP versions simultaneously
<?php $regex = '/((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, '',$subject); var_dump($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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
NULL
Output for 5.4.2 - 5.4.44, 5.5.24 - 5.5.28, 5.6.8 - 5.6.12
string(15) "aaaaxyzxyzaabaa"
preferences:
217.22 ms | 402 KiB | 254 Q