CVE-2020-37237 Composr CMS 10.0.34 Persistent Cross-Site Scripting via banners
Authenticated administrators can inject persistent XSS payloads via banner descriptions, executing scripts for all website visitors.
- 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-2020-37237?
CVE-2020-37237 is a medium-severity cross-site scripting vulnerability in Composr CMS, published on 16 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Composr CMS 10.0.34 contains a persistent cross-site scripting vulnerability that allows authenticated administrators to inject malicious scripts through the banner management interface. Attackers with admin credentials can inject XSS payloads in the Description field of the Add banner functionality, which execute for all website visitors when they access the home page.
Weakness: CWE-79
Which versions are affected by CVE-2020-37237?
How do I fix CVE-2020-37237?
No fix has been published for CVE-2020-37237 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-2020-37237 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-37237 exists.
Sources
Also known as GHSA-85qg-778w-mp8h.