mailcow: dockerized vulnerable to stored XSS in Quarantine attachment filenames_CVE-2026-40873

{
    "lastseen": "",
    "description": "mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the Quarantine details modal injects attachment filenames into HTML without escaping, allowing arbitrary HTML/JS execution. An attacker can deliver an email with a crafted attachment name so that when an admin views the quarantine item, JavaScript executes in their browser, taking over their account. Version 2026-03b fixes the vulnerability.",
    "published": "2026-04-21T19:15:39.046Z",
    "modified": "2026-04-21T19:39:19.981Z",
    "type": "cve",
    "title": "mailcow: dockerized vulnerable to stored XSS in Quarantine attachment filenames",
    "source": "GitHub_M",
    "references": "https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-2xjc-rg88-jvpp",
    "id": "CVE-2026-40873",
    "bulletinFamily": "",
    "cwe": [
        "CWE-79",
        "CWE-80"
    ],
    "cvelist": null,
    "sourceData": "mailcow mailcow-dockerized < 2026-03b",
    "sourceHref": "",
    "cvss": {
        "score": 8.9,
        "severity": "HIGH",
        "vector": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/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": "mailcow-dockerized",
    "version": "< 2026-03b",
    "vendor": "mailcow",
    "ai_description": "Stored XSS vulnerability in Quarantine attachment filenames",
    "ai_severity": "High",
    "ai_vendor": "mailcow",
    "ai_product": "mailcow-dockerized",
    "ai_version": "< 2026-03b",
    "ai_score": 8.9
}