Input validation error in Symfony - CVE-2020-15094

Detailed vulnerability description

The vulnerability allows a remote authenticated user to execute arbitrary code.

In Symfony before versions 4.4.13 and 5.1.5, the CachingHttpClient class from the HttpClient Symfony component relies on the HttpCache class to handle requests. HttpCache uses internal headers like X-Body-Eval and X-Body-File to control the restoration of cached responses. The class was initially written with surrogate caching and ESI support in mind (all HTTP calls come from a trusted backend in that scenario). But when used by CachingHttpClient and if an attacker can control the response for a request being made by the CachingHttpClient, remote code execution is possible. This has been fixed in versions 4.4.13 and 5.1.5.

How to mitigate CVE-2020-15094

Sources

• https://github.com/symfony/symfony/commit/d9910e0b33a2e0f993abff41c6fbc86951b66d78
• https://github.com/symfony/symfony/security/advisories/GHSA-754h-5r27-7x3r
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VAQJXAKWPMWB7OL6QPG2ZSEQZYYPU5RC/
• https://packagist.org/packages/symfony/http-kernel
• https://packagist.org/packages/symfony/symfony