Contao: Server-Side Request Forgery (SSRF) via Unvalidated RSS Feed URL in Feed Reader Module
8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 3.1epss 0.2%
exploitation probability
0.2%top 92% of all CVEs
observed exploitation
nono source reports it
Contao is an Open Source CMS. From 5.3.35 through 5.3.47 and from 5.7.0-RC1 through 5.7.8, the Feed Reader front-end module passes configured RSS feed URLs from FeedReaderController::getResponse() to feedIo->read() without scheme or private-address validation, allowing a backend user with module-edit permissions to make the server request internal network services, loopback addresses, or cloud metadata endpoints. In core-bundle/src/Controller/FrontendModule/FeedReaderController.php, the getResponse() function iterates over the configured feed URLs and passes each one directly to the HTTP client (via $this->feedIo->read($url, new Feed())) with no validation, while the DCA field definition for rss_feed in tl_module.php carries no URL scheme or host validation and the HTTP client is wired as @psr18.http_client (Symfony HttpClient) with no SSRF protection configured, since NoPrivateNetworkHttpClient is not used. This issue is fixed in versions 5.3.48.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
Affected products
contao · contao