Onyx: IDOR in /chat/stop-chat-session allows any authenticated user to interrupt other users chat sessions_CVE-2026-42276

{
    "lastseen": "",
    "description": "Onyx is an open-source AI platform. Prior to versions 3.0.9, 3.1.6, and 3.2.6, the POST /chat/stop-chat-session/{chat_session_id} endpoint lets any authenticated user stop any other user's active chat session. The endpoint checks authentication but never verifies the session belongs to the caller. An attacker who knows a chat session UUID can kill another user's LLM generation mid-stream. This issue has been patched in versions 3.0.9, 3.1.6, and 3.2.6.",
    "published": "2026-05-08T03:49:56.765Z",
    "modified": "2026-05-08T03:51:03.272Z",
    "type": "cve",
    "title": "Onyx: IDOR in /chat/stop-chat-session allows any authenticated user to interrupt other users chat sessions",
    "source": "GitHub_M",
    "references": "https://github.com/onyx-dot-app/onyx/security/advisories/GHSA-rw6w-hp62-gc8w",
    "id": "CVE-2026-42276",
    "bulletinFamily": "",
    "cwe": [
        "CWE-639"
    ],
    "cvelist": null,
    "sourceData": "onyx-dot-app onyx < 3.0.9\nonyx-dot-app onyx >= 3.1.0, < 3.1.6\nonyx-dot-app onyx >= 3.2.0, < 3.2.6",
    "sourceHref": "",
    "cvss": {
        "score": 4.3,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/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": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "onyx",
    "version": "< 3.0.9",
    "vendor": "onyx-dot-app",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}