User Frontend <= 4.3.13 - Authenticated (Subscriber+) Privilege Escalation via post_content Parameter

Summary

CVE	CVE-2026-120070
State	PUBLISHED
Assigner	Wordfence
Source Priority	CVE Program / NVD first with legacy fallback
Published	2026-10-31 08:16:49 UTC
Updated	2026-10-31 08:16:49 UTC
Description	The User Frontend – Membership, User Registration, User Profile, User Directory & Content Restriction with Frontend Post Submission plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 4.3.13 via the `post_content` parameter of the `submit_post()` function. The vulnerability exists because the protected-shortcode blocklist guard inspects the `sanitize_textarea_field()` copy of the submitted `post_content`, while the copy actually persisted to the database is processed through `wp_kses()`, whose `wp_kses_no_null()` step strips C0 control bytes — allowing an attacker to inject a single `\x01` byte inside the `[wpuf-registration]` tag name to defeat the `strpos()` blocklist check while the clean, functional shortcode is stored verbatim; `strip_shortcodes()` does not neutralize the stored shortcode either, because the Frontend container that registers it via `add_shortcode()` is only instantiated when `is_admin()` is false, and `admin-ajax` requests have `is_admin() === true`. This makes it possible for authenticated attackers, with Subscriber-level access and above, to inject a `[wpuf-registration role="editor"]` shortcode into a published post, causing a live Editor-role registration form to be rendered publicly on the frontend that any visitor — or the attacker themselves — can submit to mint a WordPress Editor account with an immediately active privileged session when the default `autologin_after_registration` setting is enabled.

Risk And Classification

Primary CVSS: v3.1 8.8 HIGH from [email protected]

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Problem Types: CWE-269 | CWE-269 CWE-269 Improper Privilege Management

Version	Source	Type	Score	Severity	Vector
3.1	[email protected]	Primary	8.8	HIGH	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`
3.1	CNA	DECLARED	8.8	HIGH	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`

CVSS v3.1 Breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Vendor Declared Affected Products

Source	Vendor	Product	Version	Platforms
CNA	Wedevs	User Frontend Membership User Registration User Profile User Directory Content Restriction With Frontend Post Submission	affected 4.3.13 semver	Not specified

References

Reference	Source	Link	Tags
plugins.trac.wordpress.org/changeset/3770255/wp-user-frontend/trunk/includes/Ajax/Fronte...	[email protected]	plugins.trac.wordpress.org
plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.3.13/includes/Ajax/Frontend_F...	[email protected]	plugins.trac.wordpress.org
plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.3.13/includes/Ajax/Frontend_F...	[email protected]	plugins.trac.wordpress.org
www.wordfence.com/threat-intel/vulnerabilities/id/f84b6767-f254-45c9-8e78-36d4b...	[email protected]	www.wordfence.com
plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.3.13/includes/Frontend/Regist...	[email protected]	plugins.trac.wordpress.org
plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.3.13/includes/Frontend/Regist...	[email protected]	plugins.trac.wordpress.org
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: Kuba (en)

Additional Advisory Data

Source	Time	Event
CNA	2026-10-09T18:22:03.000Z	Vendor Notified
CNA	2026-10-30T19:33:59.000Z	Disclosed

There are currently no legacy QID mappings associated with this CVE.