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Vulnerability record · CVE-2021-27821 · published 25 May 2021

CVE-2021-27821: Openwrt luci cross-site scripting vulnerability

Openwrt · Luci

The Web Interface for OpenWRT LuCI version 19.07 and lower has been discovered to have a cross-site scripting vulnerability.

6.1 CVSS 3.1 Medium EPSS 0.59% · top 53.9% CWE-79 · Cross-site scripting
6.1CVSS 3.1 base score, v2 4.3
0.59%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
9 Jul 2026Last modified by NVD

Description

The Web Interface for OpenWRT LuCI version 19.07 and lower has been discovered to have a cross-site scripting vulnerability.

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://openwrt.org/advisory/start
https://openwrt.org/releases/19.07/start

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-27821), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.