Cleanuparr: X-Forwarded-For leftmost parsing allows remote unauthenticated admin takeover when reverse-proxy mode is enabled_CVE-2026-44183

{
    "lastseen": "",
    "description": "Cleanuparr is a tool for automating the cleanup of unwanted or blocked files in Sonarr, Radarr, and supported download clients like qBittorrent.  Prior to 2.9.10, TrustedNetworkAuthenticationHandler.ResolveClientIp parses the leftmost entry of the X-Forwarded-For header as the client IP. That entry is attacker-controlled \u2014 X-Forwarded-For is append-only, so the leftmost value is whatever the original HTTP client claimed. By sending a spoofed local IP in the header, an unauthenticated remote attacker passes the trusted-network check and is logged in as the Cleanuparr administrator. This vulnerability is fixed in 2.9.10.",
    "published": "2026-05-12T17:32:52.143Z",
    "modified": "2026-05-12T17:32:52.143Z",
    "type": "cve",
    "title": "Cleanuparr: X-Forwarded-For leftmost parsing allows remote unauthenticated admin takeover when reverse-proxy mode is enabled",
    "source": "GitHub_M",
    "references": "https://github.com/Cleanuparr/Cleanuparr/security/advisories/GHSA-8q44-v65j-jc3q",
    "id": "CVE-2026-44183",
    "bulletinFamily": "",
    "cwe": [
        "CWE-290",
        "CWE-348"
    ],
    "cvelist": null,
    "sourceData": "Cleanuparr Cleanuparr < 2.9.10",
    "sourceHref": "",
    "cvss": {
        "score": 9.8,
        "severity": "CRITICAL",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
        "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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            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Cleanuparr",
    "version": "< 2.9.10",
    "vendor": "Cleanuparr",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
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    "ai_score": 0
}