---
id: CVE-2021-31673
title: >-
  A Dom-based Cross-site scripting (XSS) vulnerability at registration account
  in Cyclos 4 PRO.14.7 and before allows remote attackers to inject arbitrary
  web script or HTML via the groupId parameter.
summary: >-
  A Dom-based Cross-site scripting (XSS) vulnerability at registration account
  in Cyclos 4 PRO.14.7 and before allows remote attackers to inject arbitrary
  web script or HTML via the groupId parameter.
severity: medium
cvss: 6.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'
cwe:
  - CWE-79
vendor: cyclos
product: cyclos
affected:
  - 'cyclos >= 4.0.0, <= 4.14.7'
published: '2022-05-02'
updated: '2026-07-05'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-31673'
references:
  - url: >-
      http://packetstormsecurity.com/files/167040/Cyclos-4.14.7-Cross-Site-Scripting.html
    label: cve@mitre.org
  - url: >-
      https://tf1t.gitbook.io/mycve/cylos/cyclos-4.14.7-dom-based-cross-site-scripting-cve-2021-31673
    label: cve@mitre.org
  - url: 'http://cyclos.com'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      http://packetstormsecurity.com/files/167040/Cyclos-4.14.7-Cross-Site-Scripting.html
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://tf1t.gitbook.io/mycve/cylos/cyclos-4.14.7-dom-based-cross-site-scripting-cve-2021-31673
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
  - exploit-available
epss: 0.02559
epssPercentile: 0.84465
exploitAvailable: true
ingestedAt: '2026-07-06T17:03:24.345Z'
exploits:
  exploitdb: true
  checkedAt: '2026-09-27T10:33:26.667Z'
---

## Overview

A Dom-based Cross-site scripting (XSS) vulnerability at registration account in Cyclos 4 PRO.14.7 and before allows remote attackers to inject arbitrary web script or HTML via the groupId parameter.

## Affected

- `cyclos >= 4.0.0, <= 4.14.7`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.