CVE-2026-103086: UsersWP Authorization Bypass Vulnerability

CVE-2026-103086 Overview

CVE-2026-103086 is a missing authorization vulnerability in the Stiofan UsersWP WordPress plugin. The flaw affects all versions of UsersWP up to and including 1.2.74. An authenticated attacker with low privileges can exploit incorrectly configured access controls to modify data they should not be allowed to change. The weakness is tracked as [CWE-862] (Missing Authorization) and is exploitable over the network without user interaction.

Critical Impact
Low-privileged authenticated users can bypass access control checks in UsersWP, resulting in unauthorized modification of plugin or user data on affected WordPress sites.

Affected Products

Stiofan UsersWP WordPress plugin
All versions from unspecified initial release through 1.2.74
WordPress sites running the vulnerable plugin build

Discovery Timeline

2026-10-05 - CVE-2026-103086 published to the National Vulnerability Database (NVD)
2026-10-06 - Last updated in NVD database

Technical Details for CVE-2026-103086

Vulnerability Analysis

The vulnerability is a broken access control issue in the UsersWP plugin for WordPress. UsersWP exposes functionality that is intended to be restricted based on user role or ownership. The plugin fails to validate that the requesting user is authorized to invoke the targeted action. As a result, any authenticated subscriber-level account can trigger operations that should be reserved for higher-privileged roles or for the resource owner.

The attack is network-reachable through standard WordPress HTTP endpoints and requires no user interaction. According to the Patchstack UsersWP Vulnerability Analysis, the issue permits unauthorized actions against the integrity of plugin-managed data without affecting confidentiality or availability.

Root Cause

The root cause is a missing authorization check [CWE-862] in one or more plugin handlers. The affected code path verifies that a session is authenticated but does not confirm the user has the capability or ownership required to perform the requested operation. WordPress best practice requires explicit current_user_can() capability checks together with nonce validation on state-changing requests, both of which are absent or insufficient in vulnerable builds.

Attack Vector

Exploitation requires an attacker to hold any authenticated WordPress account on the target site. The attacker submits a crafted request to the vulnerable UsersWP endpoint, invoking an action normally gated to administrators or resource owners. Because registration is often open on WordPress sites using UsersWP, acquiring the required low-privilege account is trivial. No verified public proof-of-concept exploit code is referenced in the advisory, so the vulnerability is described in prose only. See the Patchstack advisory linked above for technical references.

Detection Methods for CVE-2026-103086

Indicators of Compromise

Unexpected changes to UsersWP profile fields, settings, or user metadata performed by low-privileged accounts
WordPress audit log entries showing subscriber-role users invoking privileged UsersWP actions or AJAX handlers
Newly created or modified user records that do not correspond to legitimate administrative activity

Detection Strategies

Inventory all WordPress installations and flag any instance running UsersWP at version 1.2.74 or earlier
Review web server access logs for POST requests to admin-ajax.php and UsersWP REST routes originating from non-administrative sessions
Correlate authentication events with privileged plugin actions to surface role and action mismatches

Monitoring Recommendations

Enable a WordPress activity log plugin to record profile, role, and plugin configuration changes with user attribution
Alert on bulk modifications to user metadata within short time windows
Monitor newly registered accounts that immediately interact with plugin administrative endpoints

How to Mitigate CVE-2026-103086

Immediate Actions Required

Update the UsersWP plugin to a version later than 1.2.74 as soon as the vendor publishes a patched release
Audit existing WordPress user accounts and remove any unauthorized or suspicious registrations
Review UsersWP configuration and user metadata for unauthorized modifications made prior to patching

Patch Information

At the time of publication, the advisory indicates the issue affects UsersWP through version 1.2.74. Site administrators should consult the Patchstack UsersWP Vulnerability Analysis and the official UsersWP plugin page on wordpress.org for the fixed release version and upgrade instructions.

Workarounds

Disable the UsersWP plugin until a fixed version is installed if the plugin is not business-critical
Restrict new user registration on the WordPress site to reduce the pool of accounts that can authenticate and exploit the flaw
Deploy a web application firewall rule to block requests to UsersWP endpoints from non-administrative sessions

bash

# Temporarily disable UsersWP via WP-CLI until a patched version is available
wp plugin deactivate userswp

# Verify installed plugin version
wp plugin get userswp --field=version