CVE-2021-41267
Fixed upstream EPSS 1%CVSS 6.5
Symfony/Http-Kernel is the HTTP kernel component for Symfony, a PHP framework for web and console applications and a set of reusable PHP components. Headers that are not part of the "trusted_headers" allowed list are ignored and protect users from "Cache poisoning" attacks. In Symfony 5.2, maintainers added support for the `X-Forwarded-Prefix` headers, but this header was accessible in SubRequest, even if it was not part of the "trusted_headers" allowed list. An attacker could leverage this opportunity to forge requests containing a `X-Forwarded-Prefix` header, leading to a web cache poisoning issue. Versions 5.3.12 and later have a patch to ensure that the `X-Forwarded-Prefix` header is not forwarded to subrequests when it is not trusted.
Products: symfony
Fixed upstream
| Ecosystem | Package | Fixed in |
|---|---|---|
| Packagist | symfony/http-kernel | 5.3.12 |
| Packagist | symfony/symfony | 5.3.12 |
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Ubuntu 22.04 LTS | symfony | no fix |
| Ubuntu 24.04 LTS | symfony | no fix |
| Ubuntu 24.10 | symfony | no fix |