libcoap Out-of-Bounds Read in OSCORE CBOR Unwrap Handling_CVE-2026-29013

{
    "lastseen": "",
    "description": "libcoap contains out-of-bounds read vulnerabilities in OSCORE Appendix B.2 CBOR unwrap handling where get_byte_inc() in src/oscore/oscore_cbor.c relies solely on assert() for bounds checking, which is removed in release builds compiled with NDEBUG. Attackers can send crafted CoAP requests with malformed OSCORE options or responses during OSCORE negotiation to trigger out-of-bounds reads during CBOR parsing and potentially cause heap buffer overflow writes through integer wraparound in allocation size computation.",
    "published": "2026-04-17T21:11:38.137Z",
    "modified": "2026-04-17T21:11:38.137Z",
    "type": "cve",
    "title": "libcoap Out-of-Bounds Read in OSCORE CBOR Unwrap Handling",
    "source": "VulnCheck",
    "references": "https://github.com/obgm/libcoap/commit/b7847c4dbb0dbee7c90b09a673d4cae256f03718\nhttps://www.vulncheck.com/advisories/libcoap-out-of-bounds-read-in-oscore-cbor-unwrap-handling",
    "id": "CVE-2026-29013",
    "bulletinFamily": "",
    "cwe": [
        "CWE-125"
    ],
    "cvelist": null,
    "sourceData": "libcoap libcoap 0",
    "sourceHref": "",
    "cvss": {
        "score": 8.8,
        "severity": "HIGH",
        "vector": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/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": "libcoap",
    "version": "0",
    "vendor": "libcoap",
    "ai_description": "Out-of-bounds read vulnerability in libcoap's OSCORE CBOR unwrap handling",
    "ai_severity": "High",
    "ai_vendor": "libcoap",
    "ai_product": "libcoap",
    "ai_version": "0",
    "ai_score": 8.8
}