CVE-2026-39956

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Source
https://cve.org/CVERecord?id=CVE-2026-39956
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-39956.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-39956
Aliases
  • GHSA-6gc3-3g9p-xx28
Downstream
Related
Published
2026-04-13T22:10:18.817Z
Modified
2026-08-12T16:24:00.110535Z
Severity
  • 6.1 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H CVSS Calculator
Summary
jq: Missing runtime type checks for _strindices lead to crash and limited memory disclosure
Details

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 jvstringindexes() without verifying they are strings, and jvstring_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.

Database specific 
{
    "cwe_ids": [
        "CWE-125",
        "CWE-476",
        "CWE-843"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39956.json",
    "cna_assigner": "GitHub_M",
    "unresolved_ranges": [
        {
            "extracted_events": [
                {
                    "introduced": "69785bf77f86e2ea1b4a20ca86775916889e91c9"
                },
                {
                    "fixed": "fdf8ef0f0810e3d365cdd5160de43db46f57ed03"
                }
            ],
            "source": "AFFECTED_FIELD"
        }
    ]
}
References

Affected packages

Git / github.com/jqlang/jq

Affected ranges

Type
GIT
Repo
https://github.com/jqlang/jq
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
fdf8ef0f0810e3d365cdd5160de43db46f57ed03
Database specific
Show details 
{
    "source": "REFERENCES"
}

Affected versions

1.*
1.6rc2
jq-1.*
jq-1.0
jq-1.1
jq-1.2
jq-1.3
jq-1.4
jq-1.5rc1
jq-1.5rc2
jq-1.6
jq-1.6rc1
jq-1.7
jq-1.7.1
jq-1.7rc1
jq-1.7rc2
jq-1.8.0
jq-1.8.1

Database specific

vanir_signatures_modified 
"2026-08-12T16:24:00Z"
vanir_signatures 
[
    {
        "id": "CVE-2026-39956-3157e7ab",
        "deprecated": false,
        "signature_type": "Line",
        "signature_version": "v1",
        "digest": {
            "threshold": 0.9,
            "line_hashes": [
                "211916491984239188589681460148175833042",
                "340154602296692499074523450035595928275",
                "240720352413467518066581454148247975032",
                "214807881025797077317835442942205548411"
            ]
        },
        "source": "https://github.com/jqlang/jq/commit/fdf8ef0f0810e3d365cdd5160de43db46f57ed03",
        "target": {
            "file": "src/builtin.c"
        }
    }
]
source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-39956.json"