CVE-2026-67214
MEDIUMnanoid before 5.1.16 Infinite Loop via Negative Size in non-secure module
Title source: cnaDescription
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.
References (3)
Core 3
Core References
Release Notes release-notes
nanoid 5.1.16 release notes
https://github.com/ai/nanoid/releases/tag/5.1.16
Patch patch
Fix commit (stop negative size from looping forever)
https://github.com/ai/nanoid/commit/6ccc67bbaba71d3d77a21d9b636f4171a268ce49
Third Party Advisory third-party-advisory
VulnCheck Advisory: nanoid before 5.1.16 Infinite Loop via Negative Size in non-secure module
https://www.vulncheck.com/advisories/nanoid-before-infinite-loop-via-negative-size-in-non-secure-module
Scores
CVSS v3
5.9
EPSS
0.0032
EPSS Percentile
24.4%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-835
Status
published
Products (2)
nanoid_project/nanoid
< 5.1.16
nanoid_project/nanoid
5.1.16
Published
Jul 29, 2026
Tracked Since
Jul 29, 2026