CodeIgniter: Uploaded file extension validation bypass in is_image and mime_in rules

{
  "id": "63d40025e252facfed97a45f884b413f518237c8525073f8b2f04734c5a3f302",
  "url": "https://osv.dev/vulnerability/CVE-2026-63223",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CodeIgniter: Uploaded file extension validation bypass in is_image and mime_in rules",
    "summary": "CodeIgniter is a PHP full-stack web framework. Prior to 4.7.4, the is_image and mime_in upload validation rules do not independently enforce a safe client filename extension, allowing a remote attacker to upload executable content when an application preserves the client filename and stores uploads in a web-accessible script-enabled directory. Applications are impacted when they validate uploads using is_image or mime_in without an independent safe extension check (such as ext_in on patched versions), save uploaded files using the client-supplied filename, and place uploads in a web-accessible directory where PHP files can execute. This issue is fixed in version 4.7.4.",
    "evidence": "osv:CVE-2026-63223",
    "products": [],
    "severity": "critical",
    "structured": {
      "id": "CVE-2026-63223",
      "aliases": [
        "CVE-2026-63223",
        "GHSA-mmj4-63m4-r6h5"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/codeigniter4/codeigniter4",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "2bd0f01d2813f9ec06db42643ce39d9f5428bf6d"
                },
                {
                  "fixed": "b6e9a4fa1dca2df3d3f261bdf61532df8c6420aa"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "4.7.4"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "b6e9a4fa1dca2df3d3f261bdf61532df8c6420aa"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "2bd0f01d2813f9ec06db42643ce39d9f5428bf6d"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v4.7.4"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v4.7.3",
            "v4.7.2",
            "v4.7.1",
            "v4.7.0",
            "v4.6.5",
            "v4.6.4",
            "v4.6.3",
            "v4.6.2",
            "v4.6.1",
            "v4.6.0",
            "v4.5.8",
            "v4.5.7",
            "v4.5.6",
            "v4.5.5",
            "v4.5.4",
            "v4.5.3",
            "v4.5.2",
            "v4.5.1",
            "v4.5.0",
            "v4.4.8",
            "v4.4.7",
            "v4.4.6",
            "v4.4.5",
            "v4.4.4",
            "v4.4.3",
            "v4.4.2",
            "v4.4.1",
            "v4.4.0",
            "v4.3.8",
            "v4.3.7",
            "v4.3.6",
            "v4.3.5",
            "v4.3.4",
            "v4.3.3",
            "v4.3.2",
            "v4.3.1",
            "v4.3.0",
            "v4.2.12",
            "v4.2.11",
            "v4.2.10",
            "v4.2.9",
            "v4.2.7",
            "v4.2.6",
            "v4.2.5",
            "v4.2.4",
            "v4.2.3",
            "v4.2.2",
            "v4.2.1",
            "v4.2.0",
            "v4.1.9",
            "v4.1.8",
            "v4.1.7",
            "v4.1.6",
            "v4.1.5",
            "v4.1.4",
            "v4.1.3",
            "v4.1.2",
            "v4.1.1",
            "v4.1.0",
            "v4.0.5",
            "v4.0.3",
            "4.0.0",
            "v4.0.1",
            "v4.0.0-rc.4",
            "v4.0.0-rc.3",
            "v4.0.0-rc.2",
            "v4.0.0-rc.2b",
            "v4.0.0-rc.1",
            "v4.0.0-beta.4",
            "v4.0.0-beta.3",
            "v4.0.0-beta.1",
            "v4.0.0.0-alpha.5",
            "v4.0.0-alpha.5",
            "v4.0.0-alpha.4",
            "v4.0.0-alpha.3",
            "v4.0.0-alpha.1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63223.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:27.273355684Z",
      "provider": "osv",
      "references": [
        "https://github.com/codeigniter4/CodeIgniter4/releases/tag/v4.7.4",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63223.json",
        "https://github.com/codeigniter4/CodeIgniter4/security/advisories/GHSA-mmj4-63m4-r6h5",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-63223",
        "https://github.com/codeigniter4/CodeIgniter4/commit/b6e9a4fa1dca2df3d3f261bdf61532df8c6420aa"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-434"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63223.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-63223",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 493876,
  "published_at": "2026-07-31T04:10:28.179+00:00"
}