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GHSA-v77v-x634-9m56high7.5

Symfony vulnerable to denial of service via a malicious HTTP Host header

Check your stack

The advisory, in context

All 2.0.X, 2.1.X, 2.2.X, 2.3.X, 2.4.X, and 2.5.X versions of the Symfony HttpFoundation component are affected by this security issue.

This issue has been fixed in Symfony 2.3.19, 2.4.9, and 2.5.4. Note that no fixes are provided for Symfony 2.0, 2.1, and 2.2 as they are not maintained anymore.

Description When an arbitrarily long hostname is sent by a client, its parsing in Request::getHost() can lead to a DoS attack, due to the way we validate the hostname via a regular expression.

Resolution The regular expression used to parse and validate the hostname from the HTTP request has been modified to avoid too much sensitivity to the submitted value length.

The patch for this issue is available here: https://github.com/symfony/symfony/pull/11828

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.

Ecosystem versions

From 2.0.0 before 2.3.19

Fixed in 2.3.19

65 explicitly affected versions

2.0.4, 2.0.5, 2.0.6, 2.0.7, v2.0.10, v2.0.12, v2.0.13, v2.0.14, v2.0.15, v2.0.16, v2.0.17, v2.0.18, v2.0.19, v2.0.20, v2.0.21, v2.0.22, v2.0.23, v2.0.24, v2.0.25, v2.0.9, v2.1.0, v2.1.1, v2.1.10, v2.1.11, v2.1.12, v2.1.13, v2.1.2, v2.1.3, v2.1.4, v2.1.5, v2.1.6, v2.1.7, v2.1.8, v2.1.9, v2.2.0, v2.2.1, v2.2.10, v2.2.11, v2.2.2, v2.2.3, v2.2.4, v2.2.5, v2.2.6, v2.2.7, v2.2.8, v2.2.9, v2.3.0, v2.3.1, v2.3.10, v2.3.11, v2.3.12, v2.3.13, v2.3.14, v2.3.15, v2.3.16, v2.3.17, v2.3.18, v2.3.2, v2.3.3, v2.3.4, v2.3.5, v2.3.6, v2.3.7, v2.3.8, v2.3.9

View affected-version evidence
{
  "ranges": [
    {
      "events": [
        {
          "introduced": "2.0.0"
        },
        {
          "fixed": "2.3.19"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "2.0.4",
    "2.0.5",
    "2.0.6",
    "2.0.7",
    "v2.0.10",
    "v2.0.12",
    "v2.0.13",
    "v2.0.14",
    "v2.0.15",
    "v2.0.16",
    "v2.0.17",
    "v2.0.18",
    "v2.0.19",
    "v2.0.20",
    "v2.0.21",
    "v2.0.22",
    "v2.0.23",
    "v2.0.24",
    "v2.0.25",
    "v2.0.9",
    "v2.1.0",
    "v2.1.1",
    "v2.1.10",
    "v2.1.11",
    "v2.1.12",
    "v2.1.13",
    "v2.1.2",
    "v2.1.3",
    "v2.1.4",
    "v2.1.5",
    "v2.1.6",
    "v2.1.7",
    "v2.1.8",
    "v2.1.9",
    "v2.2.0",
    "v2.2.1",
    "v2.2.10",
    "v2.2.11",
    "v2.2.2",
    "v2.2.3",
    "v2.2.4",
    "v2.2.5",
    "v2.2.6",
    "v2.2.7",
    "v2.2.8",
    "v2.2.9",
    "v2.3.0",
    "v2.3.1",
    "v2.3.10",
    "v2.3.11",
    "v2.3.12",
    "v2.3.13",
    "v2.3.14",
    "v2.3.15",
    "v2.3.16",
    "v2.3.17",
    "v2.3.18",
    "v2.3.2",
    "v2.3.3",
    "v2.3.4",
    "v2.3.5",
    "v2.3.6",
    "v2.3.7",
    "v2.3.8",
    "v2.3.9"
  ]
}
Ecosystem versions

From 2.4.0 before 2.4.9

Fixed in 2.4.9

9 explicitly affected versions

v2.4.0, v2.4.1, v2.4.2, v2.4.3, v2.4.4, v2.4.5, v2.4.6, v2.4.7, v2.4.8

View affected-version evidence
{
  "ranges": [
    {
      "events": [
        {
          "introduced": "2.4.0"
        },
        {
          "fixed": "2.4.9"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "v2.4.0",
    "v2.4.1",
    "v2.4.2",
    "v2.4.3",
    "v2.4.4",
    "v2.4.5",
    "v2.4.6",
    "v2.4.7",
    "v2.4.8"
  ]
}
Ecosystem versions

From 2.5.0 before 2.5.4

Fixed in 2.5.4

4 explicitly affected versions

v2.5.0, v2.5.1, v2.5.2, v2.5.3

View affected-version evidence
{
  "ranges": [
    {
      "events": [
        {
          "introduced": "2.5.0"
        },
        {
          "fixed": "2.5.4"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "v2.5.0",
    "v2.5.1",
    "v2.5.2",
    "v2.5.3"
  ]
}
Ecosystem versions

From 2.0.0 before 2.3.19

Fixed in 2.3.19

80 explicitly affected versions

2.0.4, 2.0.5, 2.0.6, 2.0.7, v2.0.10, v2.0.11, v2.0.12, v2.0.13, v2.0.14, v2.0.15, v2.0.16, v2.0.17, v2.0.18, v2.0.19, v2.0.20, v2.0.21, v2.0.22, v2.0.23, v2.0.24, v2.0.25, v2.0.9, v2.1.0, v2.1.0-BETA1, v2.1.0-BETA2, v2.1.0-BETA3, v2.1.0-BETA4, v2.1.0-RC1, v2.1.0-RC2, v2.1.1, v2.1.10, v2.1.11, v2.1.12, v2.1.13, v2.1.2, v2.1.3, v2.1.4, v2.1.5, v2.1.6, v2.1.7, v2.1.8, v2.1.9, v2.2.0, v2.2.0-BETA1, v2.2.0-BETA2, v2.2.0-RC1, v2.2.0-RC2, v2.2.0-RC3, v2.2.1, v2.2.10, v2.2.11, v2.2.2, v2.2.3, v2.2.4, v2.2.5, v2.2.6, v2.2.7, v2.2.8, v2.2.9, v2.3.0, v2.3.0-BETA1, v2.3.0-BETA2, v2.3.0-RC1, v2.3.1, v2.3.10, v2.3.11, v2.3.12, v2.3.13, v2.3.14, v2.3.15, v2.3.16, v2.3.17, v2.3.18, v2.3.2, v2.3.3, v2.3.4, v2.3.5, v2.3.6, v2.3.7, v2.3.8, v2.3.9

View affected-version evidence
{
  "ranges": [
    {
      "events": [
        {
          "introduced": "2.0.0"
        },
        {
          "fixed": "2.3.19"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "2.0.4",
    "2.0.5",
    "2.0.6",
    "2.0.7",
    "v2.0.10",
    "v2.0.11",
    "v2.0.12",
    "v2.0.13",
    "v2.0.14",
    "v2.0.15",
    "v2.0.16",
    "v2.0.17",
    "v2.0.18",
    "v2.0.19",
    "v2.0.20",
    "v2.0.21",
    "v2.0.22",
    "v2.0.23",
    "v2.0.24",
    "v2.0.25",
    "v2.0.9",
    "v2.1.0",
    "v2.1.0-BETA1",
    "v2.1.0-BETA2",
    "v2.1.0-BETA3",
    "v2.1.0-BETA4",
    "v2.1.0-RC1",
    "v2.1.0-RC2",
    "v2.1.1",
    "v2.1.10",
    "v2.1.11",
    "v2.1.12",
    "v2.1.13",
    "v2.1.2",
    "v2.1.3",
    "v2.1.4",
    "v2.1.5",
    "v2.1.6",
    "v2.1.7",
    "v2.1.8",
    "v2.1.9",
    "v2.2.0",
    "v2.2.0-BETA1",
    "v2.2.0-BETA2",
    "v2.2.0-RC1",
    "v2.2.0-RC2",
    "v2.2.0-RC3",
    "v2.2.1",
    "v2.2.10",
    "v2.2.11",
    "v2.2.2",
    "v2.2.3",
    "v2.2.4",
    "v2.2.5",
    "v2.2.6",
    "v2.2.7",
    "v2.2.8",
    "v2.2.9",
    "v2.3.0",
    "v2.3.0-BETA1",
    "v2.3.0-BETA2",
    "v2.3.0-RC1",
    "v2.3.1",
    "v2.3.10",
    "v2.3.11",
    "v2.3.12",
    "v2.3.13",
    "v2.3.14",
    "v2.3.15",
    "v2.3.16",
    "v2.3.17",
    "v2.3.18",
    "v2.3.2",
    "v2.3.3",
    "v2.3.4",
    "v2.3.5",
    "v2.3.6",
    "v2.3.7",
    "v2.3.8",
    "v2.3.9"
  ]
}
Ecosystem versions

From 2.4.0 before 2.4.9

Fixed in 2.4.9

9 explicitly affected versions

v2.4.0, v2.4.1, v2.4.2, v2.4.3, v2.4.4, v2.4.5, v2.4.6, v2.4.7, v2.4.8

View affected-version evidence
{
  "ranges": [
    {
      "events": [
        {
          "introduced": "2.4.0"
        },
        {
          "fixed": "2.4.9"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "v2.4.0",
    "v2.4.1",
    "v2.4.2",
    "v2.4.3",
    "v2.4.4",
    "v2.4.5",
    "v2.4.6",
    "v2.4.7",
    "v2.4.8"
  ]
}
Ecosystem versions

From 2.5.0 before 2.5.4

Fixed in 2.5.4

4 explicitly affected versions

v2.5.0, v2.5.1, v2.5.2, v2.5.3

View affected-version evidence
{
  "ranges": [
    {
      "events": [
        {
          "introduced": "2.5.0"
        },
        {
          "fixed": "2.5.4"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "v2.5.0",
    "v2.5.1",
    "v2.5.2",
    "v2.5.3"
  ]
}

References