free5GC: SMF UPI POST /upi/v1/upNodesLinks exits the SMF process on overlapping UE pools (unauthenticated, reachable Fatalf)_CVE-2026-44321

{
    "lastseen": "",
    "description": "free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without inbound OAuth2 middleware. The POST /upi/v1/upNodesLinks create-or-update handler accepts attacker-controlled JSON and passes it directly into UpNodesFromConfiguration(), which calls logger.InitLog.Fatalf(...) on several validation failures. One confirmed path is the UE-IP-pool overlap check: a single unauthenticated POST that adds a new UPF whose pool overlaps an existing UPF terminates the entire SMF process (docker ps shows Exited (1)), not just the goroutine. This vulnerability is fixed in 4.2.2.",
    "published": "2026-05-27T15:47:33.112Z",
    "modified": "2026-05-27T15:47:33.112Z",
    "type": "cve",
    "title": "free5GC: SMF UPI POST /upi/v1/upNodesLinks exits the SMF process on overlapping UE pools (unauthenticated, reachable Fatalf)",
    "source": "GitHub_M",
    "references": "https://github.com/free5gc/free5gc/security/advisories/GHSA-44qj-cghf-9p97\nhttps://github.com/free5gc/free5gc/issues/906\nhttps://github.com/free5gc/smf/pull/203\nhttps://github.com/free5gc/smf/commit/e0974e07ddab44a67d36a563cca383b2449e33e5",
    "id": "CVE-2026-44321",
    "bulletinFamily": "",
    "cwe": [
        "CWE-306",
        "CWE-617",
        "CWE-862"
    ],
    "cvelist": null,
    "sourceData": "free5gc free5gc < 4.2.2",
    "sourceHref": "",
    "cvss": {
        "score": 7.5,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/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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            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "free5gc",
    "version": "< 4.2.2",
    "vendor": "free5gc",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
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    "ai_score": 0
}