DTLS 1.3 ACK serialization heap buffer overflow via integer truncation_CVE-2026-6679

{
    "lastseen": "",
    "description": "A heap buffer overflow could occur in the DTLS 1.3 ACK serialization path before the connecting peer is authenticated. The buffer overflow was due to an integer truncation when computing the length of the ACK record-number list, causing an undersized buffer to be allocated and then overrun. This affects builds using DTLS 1.3 and wolfSSL version 5.9.0 and earlier. A fix was added to the 5.9.1 release.",
    "published": "2026-06-25T20:13:06.190Z",
    "modified": "2026-06-25T20:13:06.190Z",
    "type": "cve",
    "title": "DTLS 1.3 ACK serialization heap buffer overflow via integer truncation",
    "source": "wolfSSL",
    "references": "https://github.com/wolfSSL/wolfssl/pull/10116\nhttps://www.wolfssl.com/docs/security-vulnerabilities/",
    "id": "CVE-2026-6679",
    "bulletinFamily": "",
    "cwe": [
        "CWE-787",
        "CWE-190",
        "CWE-197"
    ],
    "cvelist": null,
    "sourceData": "wolfSSL wolfSSL 5.4.0",
    "sourceHref": "",
    "cvss": {
        "score": 8.8,
        "severity": "HIGH",
        "vector": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/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": "wolfSSL",
    "version": "5.4.0",
    "vendor": "wolfSSL",
    "ai_description": "Heap buffer overflow in DTLS 1.3 ACK serialization due to integer truncation",
    "ai_severity": "High",
    "ai_vendor": "wolfSSL",
    "ai_product": "wolfSSL",
    "ai_version": "5.9.0 and earlier",
    "ai_score": 8.8
}