Wrong regex for extracting From domain

[marc-vanderwal]

The following line uses a regular expression to attempt extracting the domain name of the From header:

authres_status/authres_status.php

Line 353 in eba5833

if (preg_match("/[@]([a-zA-Z0-9]+([.][a-zA-Z0-9]+)?\.[a-zA-Z]{2,4})/", $headers->from, $m)) {

However this regular expression is incorrect, for several reasons:

• domain name labels (including top-level domains) may also contain hyphens;
• TLDs exist that are more than 4 characters long, e.g. .paris (and there are much longer TLDs on ICANN’s list).

On a closed test network where I was using domain names ending in .example, this causes an e-mail whose sender domain is sender.example to be labeled STATUS_THIRD by this plugin despite SPF, DKIM and DMARC passing, all at sender.example. Adjusting the {2,4} to {2,7} as a test yielded STATUS_PASS instead.

[pimlie]

Thanks for the report, seems I fixed this last year already but forgot to resolve this issue. See #71, just reverted back to the most basic domain extraction I know ;)