jq: Wild stack write via signed-integer overflow in decNumber D2U() macro_CVE-2026-43894

{
    "lastseen": "",
    "description": "jq is a command-line JSON processor. In 1.8.1 and earlier, when decNumberFromString is given a number literal of INT_MAX-1 (2147483646) digits, the D2U() macro overflows during signed-int arithmetic. The wrapped negative value bypasses the heap-allocation size check, causes the function to use a 30-byte stack buffer, and then writes \u2248715 million 16-bit units (\u22481.4 GiB) at an offset 1.43 GiB below the stack frame. The written content is fully attacker-controlled (the parsed decimal digits, packed 3-per-unit).",
    "published": "2026-05-11T17:20:06.055Z",
    "modified": "2026-05-11T18:32:43.668Z",
    "type": "cve",
    "title": "jq: Wild stack write via signed-integer overflow in decNumber D2U() macro",
    "source": "GitHub_M",
    "references": "https://github.com/jqlang/jq/security/advisories/GHSA-5v7p-2r57-2g4g",
    "id": "CVE-2026-43894",
    "bulletinFamily": "",
    "cwe": [
        "CWE-190"
    ],
    "cvelist": null,
    "sourceData": "jqlang jq <= 1.8.1",
    "sourceHref": "",
    "cvss": {
        "score": 6.2,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:L/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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        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "jq",
    "version": "<= 1.8.1",
    "vendor": "jqlang",
    "ai_description": "",
    "ai_severity": "",
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    "ai_score": 0
}