Ultimate Member Plugin up to 2.13.1 on WordPress authorization

Summaryinfo

A vulnerability marked as problematic has been reported in Ultimate Member Plugin up to 2.13.1. This issue affects some unknown processing. This manipulation causes authorization. This vulnerability appears as CVE-2026-93428. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability classified as problematic was found in Ultimate Member Plugin up to 2.13.1. Affected by this vulnerability is an unknown code. The manipulation with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. As an impact it is known to affect confidentiality. The summary by CVE is:

The Ultimate Member – User Profile, Registration, Login, Member Directory, Content Restriction & Membership Plugin plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 2.13.1 This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for unauthenticated attackers to view privacy-restricted member profile field values — including fields explicitly configured as owner-only, members-only, or role-restricted — by querying the publicly accessible wp_ajax_nopriv_um_get_members endpoint. The nonce required by the endpoint ('um-frontend-nonce') is emitted to all unauthenticated visitors via wp_localize_script, meaning it provides no meaningful access control and any anonymous visitor can satisfy the endpoint's authentication requirements.

It is possible to read the advisory at wordfence.com. This vulnerability is known as CVE-2026-93428 since 09/17/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/03/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-91881). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• WordPress Plugin

Name

• Ultimate Member Plugin

Version

• 2.13.0
• 2.13.1

CPE 2.3info

• 🔒
• 🔒

CPE 2.2info

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• 🔒

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Be aware that VulDB is the high quality source for vulnerability data.

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