---
id: CVE-2021-27821
title: >-
  The Web Interface for OpenWRT LuCI version 19.07 and lower has been discovered
  to have a cross-site scripting vulnerability which can lead to attackers
  carrying out arbitrary code execution.
summary: >-
  The Web Interface for OpenWRT LuCI version 19.07 and lower has been discovered
  to have a cross-site scripting vulnerability which can lead to attackers
  carrying out arbitrary code execution.
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: openwrt
product: luci
affected:
  - luci <= 19.07.0
published: '2021-05-25'
updated: '2026-07-05'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-27821'
references:
  - url: 'http://openwrtorg.com'
    label: cve@mitre.org
  - url: 'http://openwrt.com'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://openwrtorg.com'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.00591
epssPercentile: 0.4613
ingestedAt: '2026-07-05T00:59:26.424Z'
---

## Overview

The Web Interface for OpenWRT LuCI version 19.07 and lower has been discovered to have a cross-site scripting vulnerability which can lead to attackers carrying out arbitrary code execution.

## Affected

- `luci <= 19.07.0`

## Remediation

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