Litestar has an AllowedHosts validation bypass due to unescaped regex metacharacters in configured host patterns_CVE-2026-25479

{
    "lastseen": "",
    "description": "Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. Prior to 2.20.0, in litestar.middleware.allowed_hosts, allowlist entries are compiled into regex patterns in a way that allows regex metacharacters to retain special meaning (e.g., . matches any character). This enables a bypass where an attacker supplies a host that matches the regex but is not the intended literal hostname. This vulnerability is fixed in 2.20.0.",
    "published": "2026-02-09T18:48:19.971Z",
    "modified": "2026-02-09T18:48:19.971Z",
    "type": "cve",
    "title": "Litestar has an AllowedHosts validation bypass due to unescaped regex metacharacters in configured host patterns",
    "source": "GitHub_M",
    "references": "https://github.com/litestar-org/litestar/security/advisories/GHSA-93ph-p7v4-hwh4\nhttps://github.com/litestar-org/litestar/commit/06b36f481d1bfea6f19995cfb4f203aba45c4ace\nhttps://docs.litestar.dev/2/release-notes/changelog.html#2.20.0\nhttps://github.com/litestar-org/litestar/releases/tag/v2.20.0",
    "id": "CVE-2026-25479",
    "bulletinFamily": "",
    "cwe": [
        "CWE-185"
    ],
    "cvelist": null,
    "sourceData": "litestar-org litestar < 2.20.0",
    "sourceHref": "",
    "cvss": {
        "score": 6.5,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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": "",
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            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "litestar",
    "version": "< 2.20.0",
    "vendor": "litestar-org",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}