What is CVE-2023-25811?

CVE-2023-25811 is a medium-severity vulnerability in Louislam Uptime-Kuma, classified under Cross-site Scripting. CVSS score: 6.3/10. Published 2023-02-21.

How severe is CVE-2023-25811?

Medium severity. CVSS v3 base score is 6.3 out of 10.

XSS in Louislam Uptime-Kuma

CVE-2023-25811

Uptime Kuma is a self-hosted monitoring tool. In versions prior to 1.20.0 the Uptime Kuma `name` parameter allows a persistent XSS attack. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2023-02-21 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:H/A:N.

EPSS exploit prediction

EPSS: 0.005 (38.5th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 38.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Louislam Uptime-Kuma — versions < 1.20.0
Uptime-Kuma Project

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/louislam/uptime-kuma/security/advisories/GHSA-553g-fcpf-m3wp (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2023-25811?: CVE-2023-25811 is a medium-severity vulnerability in Louislam Uptime-Kuma, classified under Cross-site Scripting. CVSS score: 6.3/10. Published 2023-02-21.
How severe is CVE-2023-25811?: Medium severity. CVSS v3 base score is 6.3 out of 10.