What is CVE-2019-25323?

CVE-2019-25323 is a medium-severity vulnerability in Heatmiser Netmonitor, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-02-12.

How severe is CVE-2019-25323?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Heatmiser Netmonitor

CVE-2019-25323

Heatmiser Netmonitor v3.03 contains an HTML injection vulnerability in the outputSetup.htm page that allows attackers to inject malicious HTML code through the outputtitle parameter. Attackers can craft specially formatted POST requests to the outputtitle parameter to execute arbitrary HTML and potentially manipulate the web interface's displayed content.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-02-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (12.2th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 12th percentile — 12.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Heatmiser Netmonitor — versions 3.03

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

www.exploit-db.com/exploits/47828 (exploit)
web.archive.org/web/20190724160628/https://www.heatmiser.com/en/ (product)
www.zoneregeling.nl/heatmiser/netmonitor-handleiding.pdf (product)
www.vulncheck.com/advisories/heatmiser-netmonitor-html-injection (third-party-advisory)

Frequently asked questions

What is CVE-2019-25323?: CVE-2019-25323 is a medium-severity vulnerability in Heatmiser Netmonitor, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-02-12.
How severe is CVE-2019-25323?: Medium severity. CVSS v3 base score is 6.1 out of 10.