Endless loop in class-wp-hook.php due to null array

[santrix]

This code in class-wp-hook.php is a major issue

} while ( false !== next( $this->iterations[ $nesting_level ] ) );

I work for a large host and several plugins can cause this to trap itself in an endless loop, creating potentially massive error_log files. The solution offered by frettled in a bug report against 4.7 seems reasonable, and does prevent it.

} while ( ! is_null( $this->iterations[ $nesting_level ] ) && false !== next( $this->iterations[ $nesting_level ] ) );

I might add that in configurations of Apache 2.4 where Mod Security is deployed, this kind of thing will also cause a memory leak leading to rapid destabilisation of a server (tested using fcgi, lsapi, suphp, cgi).

This type of thing needs to be fixed sooner than later throughout the core. I don't understand why this wasn't addressed after it was reported in 4.7

[dd32]

Duplicate of #39338.