{"id":"GHSA-28wg-ghj8-5hjv","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.","aliases":["CVE-2026-67214"],"modified":"2026-08-07T21:11:12.173309Z","published":"2026-07-29T15:31:12Z","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"},"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"}],"affected":[{"package":{"name":"nanoid","ecosystem":"npm","purl":"pkg:npm/nanoid"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"3.3.16"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/07/GHSA-28wg-ghj8-5hjv/GHSA-28wg-ghj8-5hjv.json"}},{"package":{"name":"nanoid","ecosystem":"npm","purl":"pkg:npm/nanoid"},"ranges":[{"type":"SEMVER","events":[{"introduced":"4.0.0"},{"fixed":"5.1.16"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/07/GHSA-28wg-ghj8-5hjv/GHSA-28wg-ghj8-5hjv.json"}}],"schema_version":"1.9.0","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"}]}