OpenClaw < 2026.5.12 - Custom Header Leakage via MCP Streamable HTTP Cross-Origin Redirects_CVE-2026-53840

{
    "lastseen": "",
    "description": "OpenClaw before 2026.5.12 contains an information disclosure vulnerability in streamable-http MCP servers that forwards operator-configured custom headers during cross-origin redirects. Attackers controlling or compromising an MCP endpoint can redirect requests to exfiltrate sensitive headers like API keys or tenant-routing credentials to attacker-controlled origins.",
    "published": "2026-06-16T18:04:53.345Z",
    "modified": "2026-06-16T18:51:19.624Z",
    "type": "cve",
    "title": "OpenClaw < 2026.5.12 - Custom Header Leakage via MCP Streamable HTTP Cross-Origin Redirects",
    "source": "VulnCheck",
    "references": "https://github.com/openclaw/openclaw/security/advisories/GHSA-rjxq-qqhf-8hwh\nhttps://www.vulncheck.com/advisories/openclaw-custom-header-leakage-via-mcp-streamable-http-cross-origin-redirects",
    "id": "CVE-2026-53840",
    "bulletinFamily": "",
    "cwe": [
        "CWE-522"
    ],
    "cvelist": null,
    "sourceData": "OpenClaw OpenClaw 0",
    "sourceHref": "",
    "cvss": {
        "score": 6,
        "severity": "MEDIUM",
        "vector": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/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": "OpenClaw",
    "version": "0",
    "vendor": "OpenClaw",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}