MediumFix available
jq — security advisory
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 ≈715 million 16-bit units (≈1.4 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).
- Products
- jq
- Affected versions
- 1.6-2.1, 1.6-2.1+deb12u1, 1.7.1-6+deb13u1, 1.7.1-6+deb13u2, 1.8.0-1, 1.8.1-1, 1.8.1-2, 1.8.1-3, 1.8.1-4, 1.8.1-5
- Fixed versions
- 1.6-2.1+deb12u2, 1.7.1-6+deb13u3, 1.8.1-6
- CVEs
- CVE-2026-43894
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 17:37 UTC · Revision 2
Source evidence
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 ≈715 million 16-bit units (≈1.4 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).
osv:DEBIAN-CVE-2026-43894
jq
Fixed versions: 1.6-2.1+deb12u2
jq
Fixed versions: 1.7.1-6+deb13u3
jq
Fixed versions: 1.8.1-6
Complete source record
{
"id": "c5e06e33acb8feee2a290b9bc7d87cebc6db7479465e3a0f577996368180d0b3",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-43894",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-43894",
"summary": "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 ≈715 million 16-bit units (≈1.4 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).",
"evidence": "osv:DEBIAN-CVE-2026-43894",
"products": [
{
"name": {
"value": "jq",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1.6-2.1+deb12u2",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
{
"value": "1.6-2.1",
"evidence": "/affected/0/versions"
},
{
"value": "1.6-2.1+deb12u1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "jq",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1.7.1-6+deb13u3",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": [
{
"value": "1.7.1-6+deb13u1",
"evidence": "/affected/1/versions"
},
{
"value": "1.7.1-6+deb13u2",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "jq",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1.8.1-6",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
{
"value": "1.8.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "1.8.1-1",
"evidence": "/affected/2/versions"
},
{
"value": "1.8.1-2",
"evidence": "/affected/2/versions"
},
{
"value": "1.8.1-3",
"evidence": "/affected/2/versions"
},
{
"value": "1.8.1-4",
"evidence": "/affected/2/versions"
},
{
"value": "1.8.1-5",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2026-43894",
"aliases": [
"DEBIAN-CVE-2026-43894"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.6-2.1+deb12u2"
}
]
}
],
"package": {
"name": "jq",
"purl": "pkg:deb/debian/jq?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"1.6-2.1",
"1.6-2.1+deb12u1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-43894.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.7.1-6+deb13u3"
}
]
}
],
"package": {
"name": "jq",
"purl": "pkg:deb/debian/jq?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"1.7.1-6+deb13u1",
"1.7.1-6+deb13u2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-43894.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.8.1-6"
}
]
}
],
"package": {
"name": "jq",
"purl": "pkg:deb/debian/jq?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"1.8.0-1",
"1.8.1-1",
"1.8.1-2",
"1.8.1-3",
"1.8.1-4",
"1.8.1-5"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-43894.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-27T09:47:30.104566351Z",
"provider": "osv",
"upstream": [
"CVE-2026-43894"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-43894"
]
},
"related_cves": [
{
"value": "CVE-2026-43894",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 460925,
"published_at": "2026-05-11T18:16:37.25+00:00"
}