Astro: XSS via incomplete `` sanitization in `define:vars` allows case-insensitive and whitespace-based bypass_CVE-2026-41067

{
    "lastseen": "",
    "description": "Astro is a web framework. Prior to 6.1.6, the defineScriptVars function in Astro's server-side rendering pipeline uses a case-sensitive regex /<\\/script>/g to sanitize values injected into inline <script> tags via the define:vars directive. HTML parsers close <script> elements case-insensitively and also accept whitespace or / before the closing >, allowing an attacker to bypass the sanitization with payloads like </Script>, </script >, or </script/> and inject arbitrary HTML/JavaScript. This vulnerability is fixed in 6.1.6.",
    "published": "2026-04-24T16:57:22.940Z",
    "modified": "2026-04-24T16:57:22.940Z",
    "type": "cve",
    "title": "Astro: XSS via incomplete `</script>` sanitization in `define:vars` allows case-insensitive and whitespace-based bypass",
    "source": "GitHub_M",
    "references": "https://github.com/withastro/astro/security/advisories/GHSA-j687-52p2-xcff",
    "id": "CVE-2026-41067",
    "bulletinFamily": "",
    "cwe": [
        "CWE-79"
    ],
    "cvelist": null,
    "sourceData": "withastro astro < 6.1.6",
    "sourceHref": "",
    "cvss": {
        "score": 6.1,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
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            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "astro",
    "version": "< 6.1.6",
    "vendor": "withastro",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}