Package Instance

Improper Authentication
In Symfony, a vulnerability would allow an attacker to authenticate as a privileged user on sites with user registration and remember me login functionality enabled.

Cross-site Scripting
The debug handler in Symfony has an XSS via an array key during exception pretty printing in `ExceptionHandler.php`, as demonstrated by a `/_debugbar/open?op`=get` URI.

Cross-site Scripting
In Symfony, validation messages are not escaped, which can lead to XSS when user input is included.

SQL Injection
In Symfony HTTP Methods provided as verbs or using the override header may be treated as trusted input, but they are not validated, possibly causing SQL injection or XSS.

Cross-Site Request Forgery (CSRF)
By default, a user's session is invalidated when the user is logged out. This behavior can be disabled through the `invalidate_session` option. In this case, CSRF tokens were not erased during logout which allowed for CSRF token fixation.

Unrestricted Upload of File with Dangerous Type
When using the scalar type hint `string` in a setter method (e.g. `setName(string$name)`) of a class that's the `data_class` of a form, and when a file upload is submitted to the corresponding field instead of a normal text input, then `UploadedFile::__toString()` is called which will then return and disclose the path of the uploaded file. If combined with a local file inclusion issue in certain circumstances this could escalate it to a Remote Code Execution.

URL Redirection to Untrusted Site (Open Redirect)
By using backslashes in the `_failure_path` input field of login forms, an attacker can work around the redirection target restrictions and effectively redirect the user to any domain after login.

Insufficient Session Expiration
The `PDOSessionHandler` class allows storing sessions on a PDO connection. Under some configurations and with a well-crafted payload, it was possible to do a denial of service on a Symfony application without too much resources.

URL Rewrite vulnerability
An issue in Symfony arises from support for a (legacy) IIS header that lets users override the path in the request URL via the `X-Original-URL` or `X-Rewrite-URL` HTTP request header. These headers are designed for IIS support, but it's not verified that the server is in fact running IIS, which means anybody who can send these requests to an application can trigger this. This affects `\Symfony\Component\HttpFoundation\Request::prepareRequestUri()` where `X-Original-URL` and `X_REWRITE_URL` are both used. The fix drops support for these methods so that they cannot be used as attack vectors such as web cache poisoning.

URL Redirection to Untrusted Site (Open Redirect)
The security handlers in the Security component in Symfony have an Open redirect vulnerability when `security.http_utils` is inlined by a container.

Improper Authentication
An issue was discovered in the Ldap component in Symfony. It allows remote attackers to bypass authentication by logging in with a `null` password and valid username, which triggers an unauthenticated bind.

Session Fixation
A session fixation vulnerability within the `Guard` login feature may allow an attacker to impersonate a victim towards the web application if the session id value was previously known to the attacker.

Deserialization of Untrusted Data
In Symfony it is possible to cache objects that may contain bad user input. On serialization or unserialization, this could result in the deletion of files that the current user has access to.