shell-quote parse() is quadratic in token count, enabling denial of service_CVE-2026-13311

{
    "lastseen": "",
    "description": "shell-quote prior to 1.8.5 finalizes parsed tokens in parse() using Array.prototype.concat as a reduce accumulator, which reallocates and copies the entire growing array on every iteration. As a result parse() runs in O(n^2) time relative to the number of input tokens. An attacker who can supply an attacker-controlled string to any code path that calls parse() (no shell metacharacters are required; plain space-separated words suffice) can block the single-threaded Node.js event loop for an extended period with a small input, resulting in a denial of service. There is no code execution or data disclosure; impact is to availability only. Fixed in 1.8.5.",
    "published": "2026-06-25T04:48:36.351Z",
    "modified": "2026-06-25T04:48:36.351Z",
    "type": "cve",
    "title": "shell-quote parse() is quadratic in token count, enabling denial of service",
    "source": "harborist",
    "references": "https://github.com/ljharb/shell-quote/security/advisories/GHSA-395f-4hp3-45gv\nhttps://www.npmjs.com/package/shell-quote",
    "id": "CVE-2026-13311",
    "bulletinFamily": "",
    "cwe": [
        "CWE-407"
    ],
    "cvelist": null,
    "sourceData": "ljharb shell-quote 0",
    "sourceHref": "",
    "cvss": {
        "score": 8.7,
        "severity": "HIGH",
        "vector": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
        "version": "4.0"
    },
    "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": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "shell-quote",
    "version": "0",
    "vendor": "ljharb",
    "ai_description": "Denial of service vulnerability in shell-quote prior to 1.8.5 due to quadratic time complexity in parse() function",
    "ai_severity": "High",
    "ai_vendor": "ljharb",
    "ai_product": "shell-quote",
    "ai_version": "< 1.8.5",
    "ai_score": 8.7
}