CVE-2026-4279 Cross-site scripting in Bread & Butter: AI-Powered Lead Intelligence
Authenticated attackers can inject arbitrary scripts via shortcode attributes, leading to code execution when users interact with the page.
- 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-2026-4279?
CVE-2026-4279 is a medium-severity cross-site scripting vulnerability in breadbutter Bread & Butter: AI-Powered Lead Intelligence, published on 22 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
The Bread & Butter plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'breadbutter-customevent-button' shortcode in all versions up to, and including, 8.2.0.25. This is due to insufficient input sanitization and output escaping on the 'event' shortcode attribute. The customEventShortCodeButton() function takes the 'event' attribute value and directly interpolates it into a JavaScript string within an onclick HTML attribute without applying esc_attr() or esc_js(). Notably, the sister function customEventShortCode() properly uses esc_js() for the same attribute, but this was omitted in the button variant. 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 the page and clicks the injected button.
Weakness: CWE-79
Which versions are affected by CVE-2026-4279?
How do I fix CVE-2026-4279?
No fix has been published for CVE-2026-4279 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-2026-4279 being exploited?
There is no known exploitation of CVE-2026-4279 in the wild and no public exploit code.
Sources
Also known as GHSA-g8vq-gpv7-9mmq.