RustFS Snowball Auto-Extract: Path Traversal allows cross-bucket object injection_CVE-2026-49991

{
    "lastseen": "",
    "description": "RustFS is a distributed object storage system built in Rust. In 1.0.0-beta.4, authenticated users with only PutObject permission on their own bucket can exploit a path traversal vulnerability in the Snowball auto-extract feature to write arbitrary objects into other users' buckets, completely breaking multi-tenant isolation. The vulnerability chains three flaws: No ../ sanitization in tar entry key normalization; IAM wildcard matching uses raw (uncleaned) paths; and Filesystem path cleaning resolves ../ across bucket boundaries.",
    "published": "2026-06-26T20:01:29.896Z",
    "modified": "2026-06-26T20:01:29.896Z",
    "type": "cve",
    "title": "RustFS Snowball Auto-Extract: Path Traversal allows cross-bucket object injection",
    "source": "GitHub_M",
    "references": "https://github.com/rustfs/rustfs/security/advisories/GHSA-f4vq-9ffr-m8m3",
    "id": "CVE-2026-49991",
    "bulletinFamily": "",
    "cwe": [
        "CWE-22",
        "CWE-862"
    ],
    "cvelist": null,
    "sourceData": "rustfs rustfs 1.0.0-beta.4",
    "sourceHref": "",
    "cvss": {
        "score": 8.6,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/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": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
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        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "rustfs",
    "version": "1.0.0-beta.4",
    "vendor": "rustfs",
    "ai_description": "Path traversal vulnerability in RustFS Snowball auto-extract feature allows authenticated users to write arbitrary objects into other users' buckets",
    "ai_severity": "High",
    "ai_vendor": "RustFS",
    "ai_product": "RustFS",
    "ai_version": "1.0.0-beta.4",
    "ai_score": 8.6
}