CVE-2026-34890 WordPress MSTW League Manager plugin <= 2.10 - Cross Site Scripting (XSS) vulnerability
A DOM-based XSS vulnerability in the MSTW League Manager WordPress plugin allows attackers to inject malicious scripts into web pages viewed by other users.
- 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-2026-34890?
CVE-2026-34890 is a medium-severity cross-site scripting vulnerability in Mark O’Donnell MSTW League Manager, published on 2 Apr 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
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Mark O’Donnell MSTW League Manager allows DOM-Based XSS.This issue affects MSTW League Manager: from n/a through 2.10.
Weakness: CWE-79
Which versions are affected by CVE-2026-34890?
How do I fix CVE-2026-34890?
No fix has been published for CVE-2026-34890 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-2026-34890 being exploited?
There is no known exploitation of CVE-2026-34890 in the wild and no public exploit code.
Sources
Also known as GHSA-6jgp-7rr8-ccg5.