Advisory Weakness Curation

Prevent cache poisoning via a Response Content-Type header in Symfony Description ----------- When a `Response` does not contain a `Content-Type` header, Symfony falls back to the format defined in the `Accept` header of the request, leading to a possible mismatch between the response's content and `Content-Type` header. When the response is cached, this can lead to a corrupted cache where the cached format is not the right one. Resolution ---------- Symfony does not use the `Accept` header anymore to guess the `Content-Type`. The patch for this issue is available here https://github.com/symfony/symfony/commit/dca343442e6a954f96a2609e7b4e9c21ed6d74e6 for the 4.4 branch. Credits ------- I would like to thank Xavier Lacot from JoliCode for reporting & Yonel Ceruto and Tobias Schultze for fixing the issue.

Improper Input Validation In Symfony, when a `Response` does not contain a `Content-Type` header, affected versions of Symfony can fallback to the format defined in the `Accept` header of the request, leading to a possible mismatch between the response content and `Content-Type` header. When the response is cached, this can prevent the use of the website by other users.