CVE-2022-31140

<?php

namespace My\App;

use CuyZ\Valinor\Mapper\MappingError; use CuyZ\Valinor\Mapper\Tree\Node; use CuyZ\Valinor\Mapper\Tree\NodeTraverser; use CuyZ\Valinor\MapperBuilder;

require_once __DIR__ . '/Valinor/vendor/autoload.php’;

final class Money { private function __construct(public readonly string $amount) { }

public static function fromString(string $money): self
{
    if (1 !== \\preg\_match('/^\\d+ \[A-Z\]{3}$/', $money)) {
        throw new \\InvalidArgumentException(\\sprintf('Given "%s" is not a recognized monetary amount', $money));
    }
    
    return new self($money);
}

}

class Foo { public function __construct( private readonly Money $a, private readonly Money $b, private readonly Money $c, ) {} }

$mapper = (new MapperBuilder()) ->registerConstructor([Money::class, ‘fromString’]) ->mapper();

try { var_dump($mapper->map(Foo::class, [ ‘a’ => 'HAHA’, ‘b’ => '100 EUR’, ‘c’ => ‘USD 100’ ])); } catch (MappingError $e) { $messages = (new NodeTraverser(function (Node $node) { foreach ($node->messages() as $message) { var_dump([ '$message’, $message->path(), $message->body() ]); } return '’; }))->traverse($e->node());

iterator\_to\_array($messages);

}

Now, this is quite innocent: it produces following output:

❯ php value-object-conversion.php
array(3) {
  [0]=>
  string(8) "$message"
  [1]=>
  string(1) "a"
  [2]=>
  string(48) "Given "HAHA" is not a recognized monetary amount"
}
array(3) {
  [0]=>
  string(8) "$message"
  [1]=>
  string(1) "c"
  [2]=>
  string(51) "Given "USD 100" is not a recognized monetary amount"
}

The problem is that nowhere I told valinor that it could use Throwable#getMessage().

This is a problem with cases where you get:

• an SQL exception showing an SQL snippet
• a DB connection exception showing DB ip address/username/password
• a timeout detail / out of memory detail (exploring DDoS possibilities)

This allows for potential data exfiltration, DDoS, enumeration attacks, etc.