{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/products/user-registration-advanced-fields-plugin--1.6.20/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[{"cvss":9.8,"id":"CVE-2026-4882"}],"_cs_exploited":false,"_cs_products":["User Registration Advanced Fields plugin \u003c= 1.6.20"],"_cs_severities":["critical"],"_cs_tags":["wordpress","file-upload","rce"],"_cs_type":"advisory","_cs_vendors":["WordPress"],"content_html":"\u003cp\u003eThe User Registration Advanced Fields plugin for WordPress, specifically versions up to and including 1.6.20, contains an arbitrary file upload vulnerability (CVE-2026-4882) due to insufficient file type validation in the \u003ccode\u003eURAF_AJAX::method_upload\u003c/code\u003e function. This flaw enables unauthenticated attackers to upload any file type to the affected server, which can lead to remote code execution if the uploaded file is strategically placed and executed. The vulnerability is exploitable only if a \u0026ldquo;Profile Picture\u0026rdquo; field is active within the registration form. This poses a significant threat to websites using the plugin, as attackers can potentially gain full control of the server.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn unauthenticated attacker identifies a WordPress site using the vulnerable User Registration Advanced Fields plugin (\u0026lt;= 1.6.20) with the \u0026ldquo;Profile Picture\u0026rdquo; field enabled.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious HTTP request to the \u003ccode\u003eURAF_AJAX::method_upload\u003c/code\u003e function, bypassing any client-side file type checks.\u003c/li\u003e\n\u003cli\u003eThe attacker uploads a web shell (e.g., a PHP file) disguised as a legitimate file type or without any extension to evade basic detection mechanisms.\u003c/li\u003e\n\u003cli\u003eThe vulnerable plugin saves the file to the WordPress uploads directory without proper validation.\u003c/li\u003e\n\u003cli\u003eThe attacker identifies the exact file path of the uploaded web shell on the server.\u003c/li\u003e\n\u003cli\u003eThe attacker sends another HTTP request directly to the uploaded web shell.\u003c/li\u003e\n\u003cli\u003eThe web shell executes on the server, providing the attacker with remote code execution capabilities.\u003c/li\u003e\n\u003cli\u003eThe attacker can then leverage the web shell to perform various malicious activities, such as installing malware, defacing the website, or exfiltrating sensitive data.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of this vulnerability (CVE-2026-4882) allows unauthenticated attackers to upload arbitrary files to a vulnerable WordPress website, potentially leading to remote code execution. This can result in complete compromise of the affected website, including data theft, website defacement, and malware infections. The CVSS v3.1 base score for this vulnerability is 9.8, indicating a critical severity level. The impact includes potential damage to reputation, financial losses, and legal liabilities.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpgrade the User Registration Advanced Fields plugin to the latest version (greater than 1.6.20) to patch CVE-2026-4882.\u003c/li\u003e\n\u003cli\u003eImplement file type validation on the server-side, restricting allowed file extensions for profile picture uploads.\u003c/li\u003e\n\u003cli\u003eMonitor web server logs for suspicious file upload activity targeting the \u003ccode\u003eURAF_AJAX::method_upload\u003c/code\u003e function to detect potential exploitation attempts. Deploy the Sigma rule \u003ccode\u003eDetect Suspicious WordPress File Uploads\u003c/code\u003e to your SIEM.\u003c/li\u003e\n\u003cli\u003eImplement strict file permission policies to prevent uploaded files from being executed as scripts.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-05-02T05:16:00Z","date_published":"2026-05-02T05:16:00Z","id":"/briefs/2026-05-wordpress-upload/","summary":"The User Registration Advanced Fields plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation, allowing unauthenticated attackers to upload arbitrary files leading to potential remote code execution.","title":"WordPress User Registration Advanced Fields Plugin Arbitrary File Upload Vulnerability","url":"https://feed.craftedsignal.io/briefs/2026-05-wordpress-upload/"}],"language":"en","title":"CraftedSignal Threat Feed — User Registration Advanced Fields Plugin \u003c= 1.6.20","version":"https://jsonfeed.org/version/1.1"}