CVE-2021-25076

WP User Frontend <= 3.5.25 - SQL Injection & Reflected Cross-Site Scripting

2021-12-27 00:00

Strategic Overview

Status: Patched in 3.5.26
Affected Plugin: User Frontend – Membership, User Registration, User Profile, User Directory & Content Restriction with Frontend Post Submission
Affected Version: <= 3.5.25
CVSS: 8.8High
Weakness type: CWE-89 · Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
CVE: CVE-2021-25076

View all User Frontend – Membership, User Registration, User Profile, User Directory & Content Restriction with Frontend Post Submission vulnerabilities

At a glance

CVE-2021-25076 is a high-severity Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') vulnerability in the User Frontend WordPress plugin, affecting versions <= 3.5.25. It carries a CVSS score of 8.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 3.5.26; sites on affected versions should update now. Disclosed December 2021, reported by Krzysztof Zając.

Vulnerability Overview

The WP User Frontend WordPress plugin before 3.5.26 does not validate and escape the status parameter before using it in a SQL statement in the Subscribers dashboard, leading to an SQL injection. Due to the lack of sanitisation and escaping, this could also lead to Reflected Cross-Site Scripting

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. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.

CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')

Reaching this weakness in User Frontend <= 3.5.25 takes a caller who can reach the endpoint. SQL injection happens when request data is concatenated into a query instead of being bound as a parameter, letting an attacker change the structure of the statement rather than just its values.

A working injection can read any table the database user can see, which on a WordPress install means user records, password hashes and session or API secrets stored in options. For User Frontend the fix is 3.5.26: builds <= 3.5.25 are affected, anything from 3.5.26 onward is not.

Remediation

Update to version 3.5.26, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to User Frontend: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: User Frontend 3.5.26 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-25076 https://www.wordfence.com/threat-intel/vulnerabilities/id/b9793793-44d5-4628-a57b-c1254645e648 https://nvd.nist.gov/vuln/detail/CVE-2021-25076

Related records

Same weakness class

Other vulnerabilities in User Frontend – Membership, User Registration, User Profile, User Directory & Content Restriction with Frontend Post Submission

CVSS Vector

8.8

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

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