tmp: Type-confusion bypass of _assertPath in [email protected] allows path traversal via non-string prefix/postfix/template_CVE-2026-49982

{
    "lastseen": "",
    "description": "tmp is a temporary file and directory creator for node.js. In version 0.2.6, the _assertPath guard added to tmp rejects only string values that contain the substring ... It is bypassed when prefix, postfix, or template is supplied as a non-string value (Array, Buffer, or any object) whose includes('..') returns falsy but whose stringification still contains ../. The value flows through Array.prototype.join/String coercion inside _generateTmpName and path.join(tmpDir, opts.dir, name), producing a final path that escapes tmpdir and creates a file or directory at an attacker-controlled location with the host process's privileges. This affects any application that forwards untrusted request data (a common pattern is JSON body fields or qs-parsed bracket-array query strings such as ?prefix[]=...) into tmp.file, tmp.fileSync, tmp.dir, tmp.dirSync, tmp.tmpName, or tmp.tmpNameSync without explicit type coercion. This vulnerability is fixed in 0.2.7.",
    "published": "2026-06-11T15:45:00.685Z",
    "modified": "2026-06-11T15:45:00.685Z",
    "type": "cve",
    "title": "tmp: Type-confusion bypass of _assertPath in [email protected] allows path traversal via non-string prefix/postfix/template",
    "source": "GitHub_M",
    "references": "https://github.com/raszi/node-tmp/security/advisories/GHSA-7c78-jf6q-g5cm",
    "id": "CVE-2026-49982",
    "bulletinFamily": "",
    "cwe": [
        "CWE-20",
        "CWE-22"
    ],
    "cvelist": null,
    "sourceData": "raszi node-tmp 0.2.6",
    "sourceHref": "",
    "cvss": {
        "score": 8.2,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L",
        "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": "node-tmp",
    "version": "0.2.6",
    "vendor": "raszi",
    "ai_description": "",
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    "ai_score": 0
}