CVE-2026-67214

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.

Weakness

The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.

Affected Software

References

• https://github.com/ai/nanoid/commit/6ccc67bbaba71d3d77a21d9b636f4171a268ce49
• https://github.com/ai/nanoid/releases/tag/3.3.16
• https://github.com/ai/nanoid/releases/tag/5.1.16
• https://www.vulncheck.com/advisories/nanoid-before-infinite-loop-via-negative-size-in-non-secure-module