GHSA-3mr9-p497-58f6: Contao crawler leaks auth credentials to external hosts

Summary Contao's crawler tries to prevent confidential HTTP client options from being sent to external domains by creating a scoped client: full options for root page origins, cleaned options for everything else. The cleaner removes Cookie and Authorization headers, but it removes the non-Symfony option names basic_auth and bearer_auth instead of Symfony HttpClient's real auth_basic and auth_bearer options. When contao.crawl.default_http_client_options contains Basic or Bearer authentication for a protected staging/production site, those credentials remain in the "clean" client used for external links or configured additional URIs. An attacker who can get an external URL crawled, for example through a link on a crawled page while the broken-link checker is enabled, can receive the crawler credentials. Technical Detail Root Cause // core-bundle/src/Crawl/Escargot/Factory.php:175-209 @ e550b92a01ef625bd546e6c3956dd200af05ebf0 private function createHttpClient(array $options = []): HttpClientInterface { $options = array_merge_recursive( [ 'headers' => [ 'accept' => 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8', 'user-agent' => self::USER_AGENT, ], 'max_duration' => 10, ], array_merge_recursive($this->getDefaultHttpClientOptions(), $options), ); $cleanOptions = $this->cleanOptionsFromConfidentialData($options); if ($options === $cleanOptions) { return ($this->httpClientFactory)($options); } $scopedOptionsByRegex = []; foreach ($this->getRootPageUriCollection()->all() as $rootPageUri) { $scopedOptionsByRegex[preg_quote($this->getOriginFromUri($rootPageUri))] = $options; } return new ScopingHttpClient(($this->httpClientFactory)($cleanOptions), $scopedOptionsByRegex); } // core-bundle/src/Crawl/Escargot/Factory.php:226-247 @ e550b92a01ef625bd546e6c3956dd200af05ebf0 foreach ($options as $k => $v) { if ('headers' === $k) { foreach ($v as $header => $value) { if (\in_array(strtolower($header), ['authorization', 'cookie'], true)) { continue; } $c