Ultimate Member <= 2.4.1 - Username Enumeration

2022-07-14 00:00

Strategic Overview

Status: Patched in 2.4.2
Affected Plugin: Ultimate Member – User Profile, Registration, Login, Member Directory, Content Restriction & Membership Plugin
Affected Version: <= 2.4.1
CVSS: 7.5High
Weakness type: CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor
CVE: CVE pending

View all Ultimate Member – User Profile, Registration, Login, Member Directory, Content Restriction & Membership Plugin vulnerabilities

At a glance

This record tracks a high-severity Exposure of Sensitive Information to an Unauthorized Actor vulnerability in the Ultimate Member WordPress plugin, affecting versions <= 2.4.1. It carries a CVSS score of 7.5 (reachable over the network; low attack complexity; high confidentiality impact). Exploitation requires no authentication. The issue is fixed in version 2.4.2; sites on affected versions should update now. Disclosed July 2022.

Vulnerability Overview

The Ultimate Member plugin for WordPress is vulnerable to Username Enumeration in versions up to, and including, 2.4.1 via the um_get_members ajax action. This allows unauthenticated attackers to obtain a list of users including user names on that site.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality.

CWE-200: Exposure of Sensitive Information to an Unauthorized Actor

Reaching this weakness in Ultimate Member <= 2.4.1 takes a caller who can reach the endpoint. Sensitive information exposure means data the application intended to keep internal is returned to a caller who should not be able to see it.

The disclosed data — credentials, tokens, customer records or internal paths — is usually worth more as material for a follow-up attack than as an end in itself. For Ultimate Member the fix is 2.4.2: builds <= 2.4.1 are affected, anything from 2.4.2 onward is not.

Remediation

Update to version 2.4.2, or a newer patched version

How does WordSec protect against this?

The fix is the thing that ends this: Ultimate Member 2.4.2 closes this, and updating the plugin is the step that ends it.

Alerts

External References

https://www.wordfence.com/threat-intel/vulnerabilities/id/f4832fbb-94ed-41c4-8434-1972f4d92476

Related records

Same weakness class

Other vulnerabilities in Ultimate Member – User Profile, Registration, Login, Member Directory, Content Restriction & Membership Plugin

CVSS Vector

7.5

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityNone
AvailabilityNone

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