HighFix available

jq — security advisory

Type: advisorySources: OSVAdvisory ID: DEBIAN-CVE-2026-40164

jq is a command-line JSON processor. Before commit 0c7d133c3c7e37c00b6d46b658a02244fdd3c784, jq used MurmurHash3 with a hardcoded, publicly visible seed (0x432A9843) for all JSON object hash table operations, which allowed an attacker to precompute key collisions offline. By supplying a crafted JSON object (~100 KB) where all keys hashed to the same bucket, hash table lookups degraded from O(1) to O(n), turning any jq expression into an O(n²) operation and causing significant CPU exhaustion. This affected common jq use cases such as CI/CD pipelines, web services, and data processing scripts, and was far more practical to exploit than existing heap overflow issues since it required only a small payload. This issue has been patched in commit 0c7d133c3c7e37c00b6d46b658a02244fdd3c784.

Products: jq
Affected versions: 1.6-2.1, 1.6-2.1+deb12u1, 1.7.1-6+deb13u1, 1.8.0-1, 1.8.1-1, 1.8.1-2, 1.8.1-3, 1.8.1-4
Fixed versions: 1.6-2.1+deb12u2, 1.7.1-6+deb13u2, 1.8.1-5
CVEs: CVE-2026-40164
Confirmed fixed CVEs: Not specified
Updated in this feed: 1 Nov 2026, 17:36 UTC · Revision 2

Source evidence

DEBIAN-CVE-2026-40164

core-osv · Original source

Published 14 Apr 2026, 00:16 UTC

osv:DEBIAN-CVE-2026-40164

Fixed versions: 1.6-2.1+deb12u2

Fixed versions: 1.7.1-6+deb13u2

Fixed versions: 1.8.1-5

Complete source record

{
  "id": "6f87aaf2bd740acda42e2dc7f1b5441b2e52339066af14606b45cdfded6488eb",
  "url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-40164",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "DEBIAN-CVE-2026-40164",
    "summary": "jq is a command-line JSON processor. Before commit 0c7d133c3c7e37c00b6d46b658a02244fdd3c784, jq used MurmurHash3 with a hardcoded, publicly visible seed (0x432A9843) for all JSON object hash table operations, which allowed an attacker to precompute key collisions offline. By supplying a crafted JSON object (~100 KB) where all keys hashed to the same bucket, hash table lookups degraded from O(1) to O(n), turning any jq expression into an O(n²) operation and causing significant CPU exhaustion. This affected common jq use cases such as CI/CD pipelines, web services, and data processing scripts, and was far more practical to exploit than existing heap overflow issues since it required only a small payload. This issue has been patched in commit 0c7d133c3c7e37c00b6d46b658a02244fdd3c784.",
    "evidence": "osv:DEBIAN-CVE-2026-40164",
    "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+deb13u2",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": [
          {
            "value": "1.7.1-6+deb13u1",
            "evidence": "/affected/1/versions"
          }
        ]
      },
      {
        "name": {
          "value": "jq",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "1.8.1-5",
            "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"
          }
        ]
      }
    ],
    "severity": "high",
    "structured": {
      "id": "DEBIAN-CVE-2026-40164",
      "aliases": [
        "DEBIAN-CVE-2026-40164"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/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-2026-40164.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "1.7.1-6+deb13u2"
                }
              ]
            }
          ],
          "package": {
            "name": "jq",
            "purl": "pkg:deb/debian/jq?arch=source&distro=trixie",
            "ecosystem": "Debian:13"
          },
          "versions": [
            "1.7.1-6+deb13u1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-40164.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "1.8.1-5"
                }
              ]
            }
          ],
          "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"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-40164.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        }
      ],
      "modified": "2026-10-27T09:47:31.832747420Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-40164"
      ],
      "references": [
        "https://security-tracker.debian.org/tracker/CVE-2026-40164"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2026-40164",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 460877,
  "published_at": "2026-04-14T00:16:07.36+00:00"
}