nanoid is a secure, URL-friendly, unique string ID generator for JavaScript. Prior to versions 3.3.12 and 5.1.11, the nanoid(size) function in index.js and index.cjs coerces the user-influenced size parameter to a signed 32-bit integer, allowing a value of 2147483648 to become -2147483648 and corrupt the process-wide CSPRNG poolOffset in fillPool(), which causes subsequent session tokens, CSRF tokens, API keys, and unique identifiers to become the deterministic string "uuuuuuuuuuuuuuuuuuuuu" until the process restarts. This issue is fixed in versions 3.3.12 and 5.1.11.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 1
- First seenCVSS 7.4NVD modified 2026-10-23 19:10
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 6
- https://github.com/ai/nanoid/commit/7087969281cab8ba8ae3babf1894e819068b3bb4
- https://github.com/ai/nanoid/commit/821dfed7b5db7f88e92f56c60eef32c8135077c3
- https://github.com/ai/nanoid/commit/b0036ed60dc9facd7f1191a50dfb3076500202ac
- https://github.com/ai/nanoid/releases/tag/3.3.12
- https://github.com/ai/nanoid/releases/tag/5.1.11
- https://github.com/ai/nanoid/security/advisories/GHSA-xwg4-73v4-xw9w