Package Instance

Symfony vulnerable to open redirect via browser-sanitized URLs
### Description

The `Request` class, does not parse URI with special characters the same way browsers do. As a result, an attacker can trick a validator relying on the `Request` class to redirect users to another domain.

### Resolution

The `Request::create` methods now assert the URI does not contain invalid characters as defined by https://url.spec.whatwg.org/

The patch for this issue is available [here](https://github.com/symfony/symfony/commit/5a9b08e5740af795854b1b639b7d45b9cbfe8819) for branch 5.4.

### Credits

We would like to thank Sam Mush - IPASSLab && ZGC Lab for reporting the issue and Nicolas Grekas for providing the fix.

Symfony has an incorrect response from Validator when input ends with `\n`
### Description

It is possible to trick a `Validator` configured with a regular expression using the `$` metacharacters, with an input ending with `\n`.

### Resolution

Symfony now uses the `D` regex modifier to match the entire input.

The patch for this issue is available [here](https://github.com/symfony/symfony/commit/7d1032bbead9a4229b32fa6ebca32681c80cb76f) for branch 5.4.

### Credits

We would like to thank Offscript for reporting the issue and Alexandre Daubois for providing the fix.

Symfony's incorrect parsing of PATH_INFO can lead to limited authorization bypass
The `Request` class improperly interprets some `PATH_INFO` in a way that leads to representing some URLs with a path that doesn't start with a `/`. This can allow bypassing some access control rules that are built with this `/`-prefix assumption.

User enumeration leak using switch user functionality in Symfony
An issue was discovered in Symfony 4.2.0 to 4.2.11 and 4.3.0 to 4.3.7. The ability to enumerate users was possible due to different handling depending on whether the user existed when making unauthorized attempts to use the switch users functionality. This is related to symfony/security.

Symfony Unsafe Cache Serialization Could Enable RCE
An issue was discovered in Symfony 3.4.0 through 3.4.34, 4.2.0 through 4.2.11, and 4.3.0 through 4.3.7. Serializing certain cache adapter interfaces could result in remote code injection. This is related to symfony/cache.

Symfony potential Cross-site Scripting vulnerabilities in CodeExtension filters
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Starting in versions 2.0.0, 5.0.0, and 6.0.0 and prior to versions 4.4.51, 5.4.31, and 6.3.8, some Twig filters in CodeExtension use `is_safe=html` but don't actually ensure their input is safe. As of versions 4.4.51, 5.4.31, and 6.3.8, Symfony now escapes the output of the affected filters.

Prevent user enumeration using Guard or the new Authenticator-based Security
Description
-----------

The ability to enumerate users was possible without relevant permissions due to different exception messages depending on whether the user existed or not. It was also possible to enumerate users by using a timing attack, by comparing time elapsed when authenticating an existing user and authenticating a non-existing user.

Resolution
----------

We now ensure that 403s are returned whether the user exists or not if the password is invalid or if the user does not exist.

The patch for this issue is available [here](https://github.com/symfony/symfony/commit/2a581d22cc621b33d5464ed65c4bc2057f72f011) for branch 3.4.

Credits
-------

I would like to thank James Isaac and Mathias Brodala for reporting the issue and Robin Chalas for fixing the issue.

Firewall configured with unanimous strategy was not actually unanimous in Symfony
Description
-----------

On Symfony before 4.4.0, when a `Firewall` checks an access control rule (using the unanimous strategy), it iterates over all rule attributes and grant access only if *all* calls to the `accessDecisionManager` decide to grant access.

As of Symfony 4.4.0, a bug was introduced that prevents the check of attributes as soon as `accessDecisionManager` decide to grant access on one attribute.

Resolution
----------

The `accessDecisionManager` is now called with all attributes at once, allowing the unanimous strategy being applied on each attribute. 

The patch for this issue is available [here](https://github.com/symfony/symfony/commit/c935e4a3fba6cc2ab463a6ca382858068d63cebf) for the 4.4 branch.

Credits
-------

I would like to thank Antonio J. García Lagar for reporting & Robin Chalas for fixing the issue.

Symfony Http-Kernel has non-constant time comparison in UriSigner
When checking the signature of an URI (an ESI fragment URL for instance), the URISigner did not used a constant time string comparison function, resulting in a potential remote timing attack vulnerability.