CVE-2020-36861 Nagios XI < 5.7.5 Core Config Manager (CCM) XSS via Overlay Rendering and Notification/Check Period Pages
Attackers can inject arbitrary scripts into Nagios XI's Core Config Manager, potentially executing code in victims' browsers or taking over accounts.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2020-36861?
CVE-2020-36861 is a medium-severity cross-site scripting vulnerability in Nagios Nagios Xi, published on 30 Oct 2025. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
The Core Config Manager (CCM) in Nagios XI versions prior to CCM 3.0.8 / Nagios XI 5.7.5 contains multiple cross-site scripting (XSS) vulnerabilities in the overlay UI elements and the Notification/Check Period 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.
Weakness: CWE-79
Which versions are affected by CVE-2020-36861?
It affects 1 product.
Products include Nagios Nagios Xi.
How do I fix CVE-2020-36861?
No fix has been published for CVE-2020-36861 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2020-36861 being exploited?
There is no known exploitation of CVE-2020-36861 in the wild and no public exploit code.
Other vulnerabilities in Nagios Nagios Xi
Sources
Also known as GHSA-p5jq-6372-24j5.