{
  "schema_version": "1.4.0",
  "id": "GHSA-28wg-ghj8-5hjv",
  "modified": "2026-08-07T20:52:58Z",
  "published": "2026-07-29T15:31:12Z",
  "aliases": [
    "CVE-2026-67214"
  ],
  "summary": "nanoid: non-secure generators can loop indefinitely with negative size",
  "details": "nanoid (Nano ID) before 5.1.16 contains an infinite loop in the customAlphabet and nanoid functions of its non-secure module (nanoid/non-secure). When these functions are given a negative size, the loop counter is decremented from a negative value and never reaches its termination condition, spinning indefinitely and hanging the calling thread. An application that passes an unvalidated, attacker-controlled negative size to these functions is exposed to a denial-of-service condition.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"
    },
    {
      "type": "CVSS_V4",
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "nanoid"
      },
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.3.16"
            }
          ]
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "nanoid"
      },
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "4.0.0"
            },
            {
              "fixed": "5.1.16"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-67214"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ai/nanoid/pull/600"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ai/nanoid/pull/601"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ai/nanoid/commit/6ccc67bbaba71d3d77a21d9b636f4171a268ce49"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ai/nanoid/commit/e835c9b71eab832bc6106944bdd26ea96cf2c66d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ai/nanoid"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ai/nanoid/releases/tag/5.1.16"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/nanoid-before-infinite-loop-via-negative-size-in-non-secure-module"
    }
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-835"
    ],
    "severity": "HIGH",
    "github_reviewed": true,
    "github_reviewed_at": "2026-08-07T20:52:58Z",
    "nvd_published_at": "2026-07-29T14:16:35Z"
  }
}