Out-of-bounds read/write in HTTP WebSocket upgrade via non-null-terminated Sec-WebSocket-Key_CVE-2026-5067

{
    "lastseen": "",
    "description": "A remote, unauthenticated attacker can trigger memory corruption in Zephyr's HTTP server WebSocket upgrade path by sending a crafted Sec-WebSocket-Key header. The HTTP/1 header parser copies the header into a fixed-size buffer using a bounded copy that does not guarantee NUL termination when the input length reaches the buffer size. During upgrade handling the buffer is copied to a local stack buffer and passed to strlen(); if no NUL exists in-bounds, strlen() reads beyond the stack buffer and subsequent concatenation with the WebSocket magic string can write out of bounds. This leads to out-of-bounds read and write on stack memory, resulting in crash (denial of service) and potentially code execution. The path is reachable when CONFIG_HTTP_SERVER_WEBSOCKET is enabled.",
    "published": "2026-06-09T06:01:02.559Z",
    "modified": "2026-06-09T06:01:02.559Z",
    "type": "cve",
    "title": "Out-of-bounds read/write in HTTP WebSocket upgrade via non-null-terminated Sec-WebSocket-Key",
    "source": "zephyr",
    "references": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-wgr4-9pwq-94vj",
    "id": "CVE-2026-5067",
    "bulletinFamily": "",
    "cwe": [
        "CWE-170",
        "CWE-787"
    ],
    "cvelist": null,
    "sourceData": "zephyrproject-rtos Zephyr 3.7.0",
    "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": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Zephyr",
    "version": "3.7.0",
    "vendor": "zephyrproject-rtos",
    "ai_description": "Out-of-bounds read and write in Zephyr's HTTP server WebSocket upgrade path due to non-null-terminated Sec-WebSocket-Key header",
    "ai_severity": "Critical",
    "ai_vendor": "zephyrproject-rtos",
    "ai_product": "Zephyr",
    "ai_version": "3.7.0",
    "ai_score": 9.8
}