CVE-2026-4279 (GCVE-0-2026-4279)

Vulnerability from cvelistv5 – Published: 2026-04-22 07:45 – Updated: 2026-04-22 18:22
VLAI?
Title
Bread & Butter: Content Gating for Verified Leads <= 8.2.0.25 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode Attributes
Summary
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.
Severity ?
6.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
breadbutter Bread & Butter: AI-Powered Lead Intelligence Affected: 0 , ≤ 8.2.0.25 (semver)
Create a notification for this product.
Credits
Athiwat Tiprasaharn
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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