CVE-2026-67214
An application that passes an unvalidated, attacker-controlled negative size to these functions is exposed to a denial-of-service condition.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.33%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
nanoid (Nano ID) before 3.3.16 and 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.
- CVSS 4.0
- 8.2 HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.33% probability · 26th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-835
- Affected
- nanoid project/nanoid
- Source
- disclosure@vulncheck.com
References
- https://github.com/ai/nanoid/commit/6ccc67bbaba71d3d77a21d9b636f4171a268ce49Patch
- https://github.com/ai/nanoid/releases/tag/3.3.16Product, Release Notes
- https://github.com/ai/nanoid/releases/tag/5.1.16Product, Release Notes
- https://www.vulncheck.com/advisories/nanoid-before-infinite-loop-via-negative-size-in-non-secure-modulePatch, Release Notes, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.