CVE-2026-4279 | breadbutter Bread & Butter: AI-Powered Lead Intelligence Plugin Shortcode customEventShortCodeButton cross site scripting

VDB-358817 · CVE-2026-4279 · GCVE-0-2026-4279 BREADBUTTER BREAD & BUTTER: AI-POWERED LEAD INTELLIGENCE PLUGIN SHORTCODE CUSTOMEVENTSHORTCODEBUTTON CROSS SITE SCRIPTING HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 4.9 $0-$5k 2.50+ Summaryinfo A vulnerability marked as problematic has been reported in breadbutter Bread & Butter: AI-Powered Lead Intelligence Plugin up to 8.2.0.25 on WordPress. This affects the function customEventShortCodeButton of the component Shortcode Handler. The manipulation leads to cross site scripting. This vulnerability is uniquely identified as CVE-2026-4279. The attack is possible to be carried out remotely. No exploit exists. Detailsinfo A vulnerability was found in breadbutter Bread & Butter: AI-Powered Lead Intelligence Plugin up to 8.2.0.25 on WordPress and classified as problematic. This issue affects the function customEventShortCodeButton of the component Shortcode Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. The summary by CVE is: 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. The weakness was disclosed by Athiwat Tiprasaharn. The advisory is shared at wordfence.com. The identification of this vulnerability is CVE-2026-4279 since 03/16/2026. The exploitation is known to be easy. The attack may be initiated remotely. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue. There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product. Productinfo Type WordPress Plugin Vendor breadbutter Name Bread & Butter: AI-Powered Lead Intelligence Plugin Version 8.2.0.0 8.2.0.1 8.2.0.2 8.2.0.3 8.2.0.4 8.2.0.5 8.2.0.6 8.2.0.7 8.2.0.8 8.2.0.9 8.2.0.10 8.2.0.11 8.2.0.12 8.2.0.13 8.2.0.14 8.2.0.15 8.2.0.16 8.2.0.17 8.2.0.18 8.2.0.19 8.2.0.20 8.2.0.21 8.2.0.22 8.2.0.23 8.2.0.24 8.2.0.25 CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 4.9 VulDB Meta Temp Score: 4.9 VulDB Base Score: 3.5 VulDB Temp Score: 3.4 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 6.4 CNA Vector (Wordfence): 🔒 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Cross site scripting CWE: CWE-79 / CWE-94 / CWE-74 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: no mitigation known Status: 🔍 0-Day Time: 🔒 Timelineinfo 03/16/2026 CVE reserved 04/22/2026 +36 days Advisory disclosed 04/22/2026 +0 days VulDB entry created 04/22/2026 +0 days VulDB entry last update Sourcesinfo Advisory: wordfence.com Researcher: Athiwat Tiprasaharn Status: Not defined CVE: CVE-2026-4279 (🔒) GCVE (CVE): GCVE-0-2026-4279 GCVE (VulDB): GCVE-100-358817 Entryinfo Created: 04/22/2026 12:15 Changes: 04/22/2026 12:15 (66) Complete: 🔍 Cache ID: 99:23E:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸