GHSA-q3j3-w37x-hq2q — Webcache Poisoning in symfony/http-kernel

The advisory, in context

Description

When a Symfony application is running behind a proxy or a load-balancer, you can tell Symfony to look for the X-Forwarded-* HTTP headers. HTTP headers that are not part of the "trusted_headers" allowed list are ignored and protect you from "Cache poisoning" attacks.

In Symfony 5.2, we've added support for the X-Forwarded-Prefix header, but this header was accessible in sub-requests, 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 HTTP header, leading to a web cache poisoning issue.

Resolution

Symfony now ensures that the X-Forwarded-Prefix HTTP header is not forwarded to sub-requests when it is not trusted.

The patch for this issue is available here for branch 5.3.

Credits

We would like to thank Soner Sayakci for reporting the issue and Jérémy Derussé for fixing the issue.

Affected packages

Start with the recorded fix for your release branch. Check your installed version and test compatibility before upgrading. Fixing this advisory does not rule out other vulnerabilities in the release.

symfony/http-kernel Packagist

Ecosystem versions

From 5.2.0 before 5.3.12

Fixed in 5.3.12

32 explicitly affected versions

v5.2.0, v5.2.1, v5.2.10, v5.2.11, v5.2.12, v5.2.13, v5.2.14, v5.2.2, v5.2.3, v5.2.4, v5.2.5, v5.2.6, v5.2.7, v5.2.8, v5.2.9, v5.3.0, v5.3.0-BETA1, v5.3.0-BETA2, v5.3.0-BETA3, v5.3.0-BETA4, v5.3.0-RC1, v5.3.1, v5.3.10, v5.3.11, v5.3.2, v5.3.3, v5.3.4, v5.3.5, v5.3.6, v5.3.7, v5.3.8, v5.3.9

View affected-version evidence

{
  "ranges": [
    {
      "events": [
        {
          "introduced": "5.2.0"
        },
        {
          "fixed": "5.3.12"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "v5.2.0",
    "v5.2.1",
    "v5.2.10",
    "v5.2.11",
    "v5.2.12",
    "v5.2.13",
    "v5.2.14",
    "v5.2.2",
    "v5.2.3",
    "v5.2.4",
    "v5.2.5",
    "v5.2.6",
    "v5.2.7",
    "v5.2.8",
    "v5.2.9",
    "v5.3.0",
    "v5.3.0-BETA1",
    "v5.3.0-BETA2",
    "v5.3.0-BETA3",
    "v5.3.0-BETA4",
    "v5.3.0-RC1",
    "v5.3.1",
    "v5.3.10",
    "v5.3.11",
    "v5.3.2",
    "v5.3.3",
    "v5.3.4",
    "v5.3.5",
    "v5.3.6",
    "v5.3.7",
    "v5.3.8",
    "v5.3.9"
  ]
}

symfony/symfony Packagist