{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "3.10.0"
              },
              {
                "fixed": "7.0.4"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5978993531ba3f02a4c639d223f810e80a1fa7d3"
            }
          ],
          "repo": "https://github.com/withastro/astro",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-7pw4-f3q4-r2p2"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-116",
      "CWE-79",
      "CWE-83"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59727.json"
  },
  "details": "Astro is a web framework for content-driven websites. In versions 3.10.0 through 7.0.3, when a transition:persist, transition:scope, or transition:persist-props directive is applied to a client-hydrated (client:*) component, Astro copied the directive value onto the rendered \u003castro-island\u003e element without HTML-escaping it. If a developer reflects attacker-controlled input into one of these directives, an attacker can break out of the attribute and inject arbitrary HTML/JavaScript into the server-rendered output, resulting in reflected cross-site scripting (XSS). Exploitation requires the application developer to have written a non-idiomatic pattern — passing untrusted, request-derived input directly into a transition directive. Astro applications that do not route untrusted input into these directives are unaffected. This issue has been fixed in version 7.0.4.",
  "id": "CVE-2026-59727",
  "modified": "2026-08-12T03:51:37.050955830Z",
  "published": "2026-07-27T19:42:32.222Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/withastro/astro/releases/tag/astro@7.0.4"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59727.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/withastro/astro/security/advisories/GHSA-7pw4-f3q4-r2p2"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-59727"
    },
    {
      "type": "FIX",
      "url": "https://github.com/withastro/astro/commit/7ba0bb1dc7516e88caff9abd7767322af44b0294"
    },
    {
      "type": "FIX",
      "url": "https://github.com/withastro/astro/pull/17212"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Astro: Cross-site scripting via unescaped transition:* directive values on hydrated islands"
}