jq: Missing runtime type checks for _strindices lead to crash and limited memory disclosure_CVE-2026-39956

{
    "lastseen": "",
    "description": "jq is a command-line JSON processor. In commits after 69785bf77f86e2ea1b4a20ca86775916889e91c9, the _strindices builtin in jq's src/builtin.c passes its arguments directly to jv_string_indexes() without verifying they are strings, and jv_string_indexes() in src/jv.c relies solely on assert() checks that are stripped in release builds compiled with -DNDEBUG. This allows an attacker to crash jq trivially with input like _strindices(0), and by crafting a numeric value whose IEEE-754 bit pattern maps to a chosen pointer, achieve a controlled pointer dereference and limited memory read/probe primitive. Any deployment that evaluates untrusted jq filters against a release build is vulnerable. This issue has been patched in commit fdf8ef0f0810e3d365cdd5160de43db46f57ed03.",
    "published": "2026-04-13T22:10:18.817Z",
    "modified": "2026-04-13T22:10:18.817Z",
    "type": "cve",
    "title": "jq: Missing runtime type checks for _strindices lead to crash and limited memory disclosure",
    "source": "GitHub_M",
    "references": "https://github.com/jqlang/jq/security/advisories/GHSA-6gc3-3g9p-xx28\nhttps://github.com/jqlang/jq/commit/fdf8ef0f0810e3d365cdd5160de43db46f57ed03",
    "id": "CVE-2026-39956",
    "bulletinFamily": "",
    "cwe": [
        "CWE-125",
        "CWE-476",
        "CWE-843"
    ],
    "cvelist": null,
    "sourceData": "jqlang jq >= 69785bf77f86e2ea1b4a20ca86775916889e91c9, < fdf8ef0f0810e3d365cdd5160de43db46f57ed03",
    "sourceHref": "",
    "cvss": {
        "score": 6.1,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/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": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "jq",
    "version": ">= 69785bf77f86e2ea1b4a20ca86775916889e91c9, < fdf8ef0f0810e3d365cdd5160de43db46f57ed03",
    "vendor": "jqlang",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}