{"basis":"claimed","id":"CVE-2026-15826","name":"User Profile Builder <= 3.16.4 - Unauthenticated Authentication Bypass via Type Confusion to Administrator Account Takeover via 'username' Parameter","vendorProject":"cozmoslabs","product":"User Profile Builder – Beautiful User Registration Forms, User Profiles & User Role Editor","publishedAt":"2026-08-15","cvss":{"score":9.8,"severity":"CRITICAL","version":"3.1"},"exploited":null,"epss":{"score":0.03904,"percentile":0.90275,"date":"2026-11-02"},"coverage":{"cloudflare":{"status":"none","firstOn":null,"daysToRule":null},"aws":{"status":"none","firstOn":null,"daysToRule":null},"azure":{"status":"none","firstOn":null,"daysToRule":null},"google":{"status":"none","firstOn":null,"daysToRule":null},"fastly":{"status":"no_history","firstOn":null,"daysToRule":null},"f5":{"status":"rule","firstOn":"2026-09-16","daysToRule":32},"akamai":{"status":"no_source","firstOn":null,"daysToRule":null},"crs":{"status":"none","firstOn":null,"daysToRule":null}},"title":"User Profile Builder <= 3.16.4 - Unauthenticated Authentication Bypass via Type Confusion to Administrator Account Takeover via 'username' Parameter","description":"The User Profile Builder plugin for WordPress is vulnerable to Authentication Bypass via Type Confusion in versions up to, and including, 3.16.4. This is due to the wppb_log_in_user() function calling absint() on the return value of wp_insert_user() before performing an is_wp_error() check — when a registration is submitted with a 61–70 character username, WordPress core rejects it with a WP_Error object, but absint() coerces that object to the integer 1 before the error check can short-circuit execution, causing the plugin to bind and return a transient-backed autologin nonce tied to user ID 1. This makes it possible for unauthenticated attackers to log in as the site's Administrator account (user ID 1), resulting in full administrative takeover of the site.","cwes":["CWE-704"],"vendors":[{"vendor":"cloudflare","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"aws","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"azure","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"google","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"fastly","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"f5","status":"rule","basis":"claimed","firstOn":"2026-09-16","firstIsNew":true,"daysToRule":32,"daysAtMost":null,"freePlan":false,"claims":[{"id":"65f28f4969515a35e514140eaff81651f79ac31b5bfd484fc9b2435b6da1de3d","cve_id":"CVE-2026-15826","vendor":"f5","product":"Attack signatures","rule_id":"200013212","rule_name":"WordPress User Profile Builder Authentication Bypass","change":"new","default_action":null,"published_on":"2026-09-16","source_url":"https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog","source_title":"F5 Distributed Cloud attack signatures changelog","excerpt":"Added: signature 200013212 \"WordPress User Profile Builder Authentication Bypass\" (Authentication/Authorization Attacks, risk High), systems: WordPress. References: CVE-2026-15826.","first_seen_at":"2026-11-02T21:00:24.327Z"}]},{"vendor":"akamai","status":"no_source","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"crs","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]}],"updatedAt":"2026-11-02T21:16:35.125Z","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total"},"measured":[{"engineId":"owasp-crs","engineName":"OWASP Core Rule Set","engineVersion":"4.25.0","runtime":"Coraza v3.8.1","config":"paranoia level 1, anomaly threshold 5, default CRS settings","ranAt":"2026-11-02T13:02:57.000Z","verdict":"passed","templateId":"CVE-2026-15826","templatePath":"http/cves/2026/CVE-2026-15826.yaml","requests":5,"blockedRequests":0,"rules":[],"note":"","requestDetail":[{"method":"GET","path":"/wp-content/plugins/profile-builder/readme.txt","status":200,"blocked":false,"rules":[]},{"method":"GET","path":"/register/","status":200,"blocked":false,"rules":[]},{"method":"POST","path":"/register/","status":200,"blocked":false,"rules":[]},{"method":"GET","path":"/register/?…","status":200,"blocked":false,"rules":[]},{"method":"GET","path":"/wp-admin/options-general.php","status":200,"blocked":false,"rules":[]}]},{"engineId":"owasp-crs","engineName":"OWASP Core Rule Set","engineVersion":"4.25.0","runtime":"Coraza v3.8.1","config":"paranoia level 2, anomaly threshold 5, default CRS settings","ranAt":"2026-11-02T13:03:28.000Z","verdict":"passed","templateId":"CVE-2026-15826","templatePath":"http/cves/2026/CVE-2026-15826.yaml","requests":5,"blockedRequests":0,"rules":[],"note":"","requestDetail":[{"method":"GET","path":"/wp-content/plugins/profile-builder/readme.txt","status":200,"blocked":false,"rules":[]},{"method":"GET","path":"/register/","status":200,"blocked":false,"rules":[]},{"method":"POST","path":"/register/","status":200,"blocked":false,"rules":[]},{"method":"GET","path":"/register/?…","status":200,"blocked":false,"rules":[]},{"method":"GET","path":"/wp-admin/options-general.php","status":200,"blocked":false,"rules":[]}]}],"social":{"total":0,"first_seen":null,"daily":[{"day":"2026-10-21","posts":0},{"day":"2026-10-22","posts":0},{"day":"2026-10-23","posts":0},{"day":"2026-10-24","posts":0},{"day":"2026-10-25","posts":0},{"day":"2026-10-26","posts":0},{"day":"2026-10-27","posts":0},{"day":"2026-10-28","posts":0},{"day":"2026-10-29","posts":0},{"day":"2026-10-30","posts":0},{"day":"2026-10-31","posts":0},{"day":"2026-11-01","posts":0},{"day":"2026-11-02","posts":0},{"day":"2026-11-03","posts":0}],"top_posts":[],"exploit_repositories":[]}}