CVE-2020-36858: Nagios Log Server < 2.1.6 XSS via Create User, Edit User, & Manage Host Lists Pages

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-10-30 · updated 2026-10-18
Weakness: CWE-79

Description

Nagios Log Server versions prior to 2.1.6 contain cross-site scripting (XSS) vulnerabilities via the web interface on the Create User, Edit User, and Manage Host Lists pages. Insufficient validation or escaping of user-supplied input may allow an attacker to inject and execute arbitrary script in the context of a victim's browser.

Affected products

Nagios Log Server: before 2.1.6 — fixed in 2.1.6

How to fix

Upgrade to a fixed version: Nagios Log Server 2.1.6. Check the vendor advisory for mitigations.

References

https://www.nagios.com/changelog/nagios-log-server-2024r1/
https://www.vulncheck.com/advisories/nagios-log-server-xss-via-create-user-edit-user-and-manage-host-lists-pages

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