CVE-2026-3347 Multi Functional Flexi Lightbox <= 1.2 - Authenticated (Admin+) Stored Cross-Site Scripting via 'message' Parameter
Administrators can inject arbitrary scripts via the message parameter, leading to stored XSS execution for other users.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-3347?
CVE-2026-3347 is a medium-severity cross-site scripting vulnerability in arevico Multi Functional Flexi Lightbox, published on 21 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
The Multi Functional Flexi Lightbox plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the `arv_lb[message]` parameter in all versions up to, and including, 1.2 due to insufficient input sanitization and output escaping. This is due to the `arv_lb_options_val()` sanitize callback returning user input without any sanitization, and the stored `message` value being output in the `genLB()` function without escaping. This makes it possible for authenticated attackers, with Administrator-level access, to inject arbitrary web scripts in pages that will execute whenever a user accesses a page or post with the lightbox enabled.
Weakness: CWE-79
Which versions are affected by CVE-2026-3347?
How do I fix CVE-2026-3347?
No fix has been published for CVE-2026-3347 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-2026-3347 being exploited?
There is no known exploitation of CVE-2026-3347 in the wild and no public exploit code.
Sources
Also known as GHSA-gv9p-wq55-477w.