CVE-2025-21618: Nicegui NiceGUI On Air Authentication Issue Vulnerability

HIGH
Advisory Identifier: GHSA-v6jv-p6r8-j78w
Share
CVSS 7.5
CWE-287
Published
Advisory Summary

CVE-2025-21618 is a HIGH (CVSS 7.5) nicegui on air authentication issue vulnerability (CWE-287: Improper Authentication) affecting Nicegui libraries in the PyPI ecosystem. The issue involves nicegui on air authentication issue. Remediation is available by upgrading affected packages to version 2.9.1.

CVE-2025-21618 at a Glance

CVE Identifier CVE-2025-21618
GHSA Identifier GHSA-v6jv-p6r8-j78w
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-287: Improper Authentication
Affected Product Nicegui
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 7.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2025-21618

To remediate this vulnerability, upgrade all affected Nicegui dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

nicegui fixed: 2.9.1 
pip install nicegui>=2.9.1
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

pip show nicegui

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2025-21618, inspect your installed packages using pip:

pip show nicegui

Analyze the terminal output to locate any version of Nicegui in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.9.1), your application is affected.

Note: The pip show nicegui command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-287: Improper Authentication, where when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. In Nicegui, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary Once a user logins to one browser, all other browsers are logged in without entering password. Even incognito mode. ### Impact high

CVE-2025-21618 Affected Nicegui Versions

1 component(s)
Fixed Versions:
2.9.1
Product / Package Ecosystem Affected Versions Fixed Version
nicegui
pypi/nicegui
PyPI
< 2.9.1
2.9.1

References

GitHub Advisory / Wiki ADVISORY
https://github.com/zauberzeug/nicegui/security/advisories/GHSA-v6jv-p6r8-j78w
NVD — CVE-2025-21618 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-21618
Security Fix Commit FIX COMMIT
https://github.com/zauberzeug/nicegui/commit/1621a4ba6a06676b8094362d36623551e651adc1
Nicegui Source Repository REPOSITORY
https://github.com/zauberzeug/nicegui

Frequently Asked Questions

What is CVE-2025-21618?
CVE-2025-21618 is a security vulnerability in Nicegui involving NiceGUI On Air authentication issue under CWE-287: Improper Authentication.
Which Nicegui versions are affected?
Affected versions include releases prior to 2.9.1 across affected packages: nicegui.
What version fixes CVE-2025-21618?
Upgrading to 2.9.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is nicegui affected?
Yes, nicegui is affected in releases prior to 2.9.1. Upgrade your dependency to 2.9.1 or later.
What is the CVSS score of CVE-2025-21618?
CVE-2025-21618 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.
What CWE is associated with CVE-2025-21618?
CVE-2025-21618 is classified under CWE-287: Improper Authentication (When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.).
How can I check PyPI dependencies for CVE-2025-21618?
Run the dependency tree command: 'pip show nicegui'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-v6jv-p6r8-j78w",
  "modified" : "2025-01-06T18:43:16Z",
  "published" : "2025-01-06T16:31:16Z",
  "aliases" : [ "CVE-2025-21618" ],
  "summary" : "NiceGUI On Air authentication issue",
  "details" : "### Summary\nOnce a user logins to one browser, all other browsers are logged in without entering password. Even incognito mode.\n\n### Impact\nhigh",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "nicegui"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.9.1"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.9.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/zauberzeug/nicegui/security/advisories/GHSA-v6jv-p6r8-j78w"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-21618"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/zauberzeug/nicegui/commit/1621a4ba6a06676b8094362d36623551e651adc1"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/zauberzeug/nicegui"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-287" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-01-06T16:31:16Z",
    "nvd_published_at" : "2025-01-06T17:15:47Z"
  }
}