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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."}],"metrics":[{"cvssV3_1":{"baseScore":6.4,"baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-79","description":"CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-05-02T04:27:44.707Z","orgId":"b15e7b5b-3da4-40ae-a43c-f7aa60e62599","shortName":"Wordfence"},"references":[{"url":"https://www.wordfence.com/threat-intel/vulnerabilities/id/3e7eed9d-2d44-4951-b66b-7d8995ca617d?source=cve"},{"url":"https://plugins.trac.wordpress.org/browser/essential-blocks/trunk/includes/Blocks/AddToCart.php#L118"},{"url":"https://plugins.trac.wordpress.org/browser/essential-blocks/tags/6.0.4/includes/Blocks/AddToCart.php#L118"},{"url":"https://plugins.trac.wordpress.org/browser/essential-blocks/trunk/includes/Blocks/AddToCart.php#L120"},{"url":"https://plugins.trac.wordpress.org/browser/essential-blocks/tags/6.0.4/includes/Blocks/AddToCart.php#L120"},{"url":"https://plugins.trac.wordpress.org/browser/essential-blocks/trunk/includes/Blocks/AddToCart.php#L65"},{"url":"https://plugins.trac.wordpress.org/browser/essential-blocks/tags/6.0.4/includes/Blocks/AddToCart.php#L65"},{"url":"https://plugins.trac.wordpress.org/browser/essential-blocks/trunk/includes/Blocks/AddToCart.php#L66"},{"url":"https://plugins.trac.wordpress.org/browser/essential-blocks/tags/6.0.4/includes/Blocks/AddToCart.php#L66"},{"url":"https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new=3516287%40essential-blocks%2Ftags%2F6.1.0%2Fincludes%2FBlocks%2FAddToCart.php&old=3178777%40essential-blocks%2Ftrunk%2Fincludes%2FBlocks%2FAddToCart.php"}],"timeline":[{"lang":"en","time":"2026-03-23T15:53:08.000Z","value":"Vendor Notified"},{"lang":"en","time":"2026-05-01T16:12:21.000Z","value":"Disclosed"}],"title":"Gutenberg Essential Blocks <= 6.0.4 - Authenticated (Contributor+) Stored Cross-Site Scripting via Block Attributes"}},"cveMetadata":{"assignerOrgId":"b15e7b5b-3da4-40ae-a43c-f7aa60e62599","assignerShortName":"Wordfence","cveId":"CVE-2026-4658","datePublished":"2026-05-02T04:27:44.707Z","dateReserved":"2026-03-23T15:37:56.964Z","dateUpdated":"2026-05-02T04:27:44.707Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-02 05:16:00","lastModifiedDate":"2026-05-02 05:16:00","problem_types":["CWE-79","CWE-79 CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')"],"metrics":{"cvssMetricV31":[{"source":"security@wordfence.com","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N","baseScore":6.4,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":3.1,"impactScore":2.7}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"4658","Ordinal":"1","Title":"Gutenberg Essential Blocks <= 6.0.4 - Authenticated (Contributor","CVE":"CVE-2026-4658","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"4658","Ordinal":"1","NoteData":"The Essential Blocks – Page Builder Gutenberg Blocks, Patterns & Templates plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the className, classHook, and blockId attributes in the Add to Cart block (essential-blocks/add-to-cart) in all versions up to, and including, 6.0.4. This is due to insufficient output escaping in the render_callback() function where these attributes are placed into class and data-id HTML attributes using raw sprintf() and implode() without esc_attr() escaping. While the outer wrapper div uses get_block_wrapper_attributes() which properly escapes, the inner divs do not. 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.","Type":"Description","Title":"Gutenberg Essential Blocks <= 6.0.4 - Authenticated (Contributor"}]}}}