CVE-2026-67214 Nanoid Project CVE debrief

Who should care

Developers and administrators using nanoid in applications should be aware of this vulnerability. Given the high CVSS score, immediate attention is advised to prevent potential denial-of-service attacks. The vulnerability is particularly concerning for applications that pass unvalidated, attacker-controlled input sizes to the affected functions. Operators of affected systems should review and apply vendor patches or mitigations. Security teams should monitor for potential denial-of-service attacks and review compensating controls for exposed systems while remediation is scheduled and verified. Vulnerability management teams should inventory vulnerable nanoid installations and assess exposure. Asset owners should track exceptions, retest remediated assets, and close the item only after evidence is documented. Platform administrators should validate and sanitize input sizes to prevent negative values. Security teams should consider compensating controls for unpatched systems and review relevant monitoring, detection, and logs for exposed assets that need extra review. IT operations teams should plan vendor-supported updates or mitigations through normal change control where exposure is confirmed. Change management teams should rollback changes if necessary and verify remediation. Source tracking teams should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. Asset management teams should confirm whether affected product deployments exist in managed environments and assign an owner for follow-up. Compliance teams should ensure that remediation efforts are properly documented and tracked. Incident response teams should be prepared to respond to potential denial-of-service attacks. Penetration testing teams should review and test compensating controls for exposed systems. Red teaming teams should simulate denial-of-service attacks to test defenses. Blue teaming teams should review and improve detection and response capabilities for denial-of-service attacks. Threat intelligence teams should monitor for potential threats and provide situational awareness. Security architecture teams should review and improve

Technical summary

CVE-2026-67214 is a denial-of-service vulnerability in the nanoid library, specifically in its non-secure module. The customAlphabet and nanoid functions enter an infinite loop when given a negative size. This issue affects nanoid versions before 3.3.16 and 5.1.16. The vulnerability has a CVSS score of 8.2, indicating high severity. Developers and administrators using nanoid in applications should be aware of this vulnerability. Given the high CVSS score, immediate attention is advised to prevent potential denial-of-service attacks.

Defensive priority

CVE-2026-67214 is rated HIGH with a CVSS score of 8.2, indicating a significant denial-of-service risk. Immediate attention is advised for applications using vulnerable nanoid versions.

Recommended defensive actions

• Inventory vulnerable nanoid installations and assess exposure
• Apply vendor patches in versions 3.3.16 or 5.1.16
• Validate and sanitize input sizes to prevent negative values
• Monitor for potential denial-of-service attacks
• Consider compensating controls for unpatched systems

Evidence notes

The CVE-2026-67214 issue arises from nanoid's non-secure module, where functions customAlphabet and nanoid enter an infinite loop when given a negative size. This denial-of-service vulnerability affects applications passing unvalidated, attacker-controlled negative sizes to these functions. Vendor patches are available in versions 3.3.16 and 5.1.16.

Official resources