Traefik’s ACME TLS-ALPN fast path lacks timeouts and close on handshake stall_CVE-2026-22045

{
    "lastseen": "",
    "description": "Traefik is an HTTP reverse proxy and load balancer. Prior to 2.11.35 and 3.6.7, there is a potential vulnerability in Traefik ACME TLS certificates' automatic generation: the ACME TLS-ALPN fast path can allow unauthenticated clients to tie up go routines and file descriptors indefinitely when the ACME TLS challenge is enabled. A malicious client can open many connections, send a minimal ClientHello with acme-tls/1, then stop responding, leading to denial of service of the entry point. The vulnerability is fixed in 2.11.35 and 3.6.7.",
    "published": "2026-01-15T22:44:05.423Z",
    "modified": "2026-01-15T22:44:05.423Z",
    "type": "cve",
    "title": "Traefik's ACME TLS-ALPN fast path lacks timeouts and close on handshake stall",
    "source": "GitHub_M",
    "references": "https://github.com/traefik/traefik/security/advisories/GHSA-cwjm-3f7h-9hwq\nhttps://github.com/traefik/traefik/commit/e9f3089e9045812bcf1b410a9d40568917b26c3d\nhttps://github.com/traefik/traefik/releases/tag/v2.11.35\nhttps://github.com/traefik/traefik/releases/tag/v3.6.7",
    "id": "CVE-2026-22045",
    "bulletinFamily": "",
    "cwe": [
        "CWE-770"
    ],
    "cvelist": null,
    "sourceData": "traefik traefik < 2.11.35\ntraefik traefik >=3.0.0-beta1, < 3.6.7",
    "sourceHref": "",
    "cvss": {
        "score": 5.9,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/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": "",
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            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "traefik",
    "version": "< 2.11.35",
    "vendor": "traefik",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
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    "ai_score": 0
}