CVE-2026-4379 LightPress Lightbox <= 2.3.4 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'group' Shortcode Attribute
Authenticated attackers can inject arbitrary scripts via the gallery shortcode group attribute, executing code in victim browsers.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-4379?
CVE-2026-4379 is a medium-severity cross-site scripting vulnerability in firelightwp LightPress Lightbox, published on 8 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
The LightPress Lightbox plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the `group` attribute in the `[gallery]` shortcode in all versions up to, and including, 2.3.4. This is due to the plugin modifying gallery shortcode output to include the `group` attribute value without proper escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Weakness: CWE-79
Which versions are affected by CVE-2026-4379?
How do I fix CVE-2026-4379?
No fix has been published for CVE-2026-4379 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-2026-4379 being exploited?
There is no known exploitation of CVE-2026-4379 in the wild and no public exploit code.
Sources
Also known as GHSA-2gmw-2prf-4jf5.