CVE-2026-73086
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.30%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 7.4 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
- EPSS
- 0.30% probability · 22th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-190
- Source
- security-advisories@github.com
References
- 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
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.