7.4
HIGH CVSS 3.1
CVE-2026-73086
nanoid: Integer Overflow or Wraparound
Description

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.

INFO

Published Date :

Aug. 11, 2026, 5:19 p.m.

Last Modified :

Aug. 11, 2026, 5:19 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-73086 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update nanoid to patched versions to prevent predictable ID generation.
  • Update nanoid to version 3.3.12 or 5.1.11.
  • Verify IDs are unique after updating.
  • Restart affected processes.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-73086 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-73086 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-73086 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-73086 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 11, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'ai', 'product': 'nanoid', 'versions': [{'status': 'affected', 'version': '< 3.3.12'}, {'status': 'affected', 'version': '>= 4.0.0, < 5.1.11'}]}]
    Added Description 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.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
    Added CWE CWE-190
    Added Reference https://github.com/ai/nanoid/commit/7087969281cab8ba8ae3babf1894e819068b3bb4
    Added Reference https://github.com/ai/nanoid/commit/821dfed7b5db7f88e92f56c60eef32c8135077c3
    Added Reference https://github.com/ai/nanoid/commit/b0036ed60dc9facd7f1191a50dfb3076500202ac
    Added Reference https://github.com/ai/nanoid/releases/tag/3.3.12
    Added Reference https://github.com/ai/nanoid/releases/tag/5.1.11
    Added Reference https://github.com/ai/nanoid/security/advisories/GHSA-xwg4-73v4-xw9w
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.