CVE-2026-73086
Published:August 11, 2026
Updated:September 01, 2026
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.
Affected Packages
nanoid (CDN_JS):
Affected version(s) >=3.1.0 <3.3.12Fix Suggestion:
Update to version 3.3.12nanoid (CDN_JS):
Affected version(s) >=4.0.0 <5.1.11Fix Suggestion:
Update to version 5.1.11nanoid (CDN_JS):
Affected version(s) >=3.1.0 <3.3.12Fix Suggestion:
Update to version 3.3.12https://github.com/ai/nanoid.git (GITHUB):
Affected version(s) >=4.0.0 <5.1.11Fix Suggestion:
Update to version 5.1.11https://github.com/ai/nanoid.git (GITHUB):
Affected version(s) >=3.0.0 <3.3.12Fix Suggestion:
Update to version 3.3.12nanoid (NPM):
Affected version(s) >=0.1.0 <3.3.12Fix Suggestion:
Update to version 3.3.12nanoid (NPM):
Affected version(s) >=0.1.0 <3.3.12Fix Suggestion:
Update to version 3.3.12nanoid (NPM):
Affected version(s) >=4.0.0 <5.1.11Fix Suggestion:
Update to version 5.1.11Related Resources (9)
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Contact UsCVSS v4
Base Score:
9.1
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.4
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Integer Overflow or Wraparound
EPSS
Base Score:
0.30