Openssh: double free in red hat enterprise linux versions of openssh dh-gex client path during fips known-group validation leads to client-side denial of service_CVE-2026-55653

{
    "lastseen": "",
    "description": "A flaw was found in OpenSSH. A malicious SSH server can exploit a double free vulnerability in the Diffie-Hellman Group Exchange (DH-GEX) client path. This occurs during FIPS (Federal Information Processing Standards) mode known-group validation when the client processes attacker-controlled DH-GEX group parameters. Successful exploitation leads to client-side process termination, resulting in a Denial of Service (DoS).",
    "published": "2026-06-23T03:36:22.741Z",
    "modified": "2026-06-23T03:36:22.741Z",
    "type": "cve",
    "title": "Openssh: double free in red hat enterprise linux versions of openssh dh-gex client path during fips known-group validation leads to client-side denial of service",
    "source": "redhat",
    "references": "https://access.redhat.com/security/cve/CVE-2026-55653\nhttps://bugzilla.redhat.com/show_bug.cgi?id=2462351",
    "id": "CVE-2026-55653",
    "bulletinFamily": "",
    "cwe": [
        "CWE-415"
    ],
    "cvelist": null,
    "sourceData": "",
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    "cvss": {
        "score": 4.3,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
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        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
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    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Red Hat Enterprise Linux 10",
    "version": "",
    "vendor": "Red Hat",
    "ai_description": "",
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    "ai_score": 0
}