CVE-2023-4520 Cross-site scripting in FV Flowplayer Video Player

Medium 5.4 Published 25 Aug 2023 Updated 8 Apr 2026

Unauthenticated attackers can inject scripts and modify user metadata in the FV Flowplayer Video Player WordPress plugin.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2023-4520?

CVE-2023-4520 is a medium-severity cross-site scripting vulnerability in foliovision FV Flowplayer Video Player, published on 25 Aug 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

The FV Flowplayer Video Player plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘_fv_player_user_video’ parameter saved via the 'save' function hooked via init, and the plugin is also vulnerable to Arbitrary Usermeta Update via the 'save' function in versions up to, and including, 7.5.37.7212 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page, and makes it possible to update the user metas arbitrarily, but the meta value can only be a string.

Weakness: CWE-79

Which versions are affected by CVE-2023-4520?

It affects 1 product.

Products include Foliovision Fv Flowplayer Video Player.

How do I fix CVE-2023-4520?

No fix has been published for CVE-2023-4520 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-2023-4520 being exploited?

There is no known exploitation of CVE-2023-4520 in the wild and no public exploit code.

Sources

Also known as GHSA-v3w9-6427-5g27.