CVE-2026-5127 | User Frontend: AI Powered Frontend Posting, User Directory, Profile, Membership & User Registration <= 4.3.1 - Authenticated (Subscriber+) PHP Object Injection

The User Frontend: AI Powered Frontend Posting, User Directory, Profile, Membership & User Registration plugin for WordPress is vulnerable to Deserialization of Untrusted Data in versions up to, and including, 4.3.1 This is due to insufficient input validation and type checking on the wpuf_files parameter during form submission, combined with unconditional deserialization via maybe_unserialize() when displaying post content. This makes it possible for authenticated attackers, with Subscriber-level access and above, to inject arbitrary PHP objects, which can be leveraged to execute arbitrary code, delete arbitrary files, or perform other malicious actions if a POP chain is present on the target system.

Published: 2026-05-08 Last update: 2026-05-08 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-5127 is rated Moderate Risk (41.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-5127

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-08 0.06%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-5127

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]

Weakness enumeration for CVE-2026-5127

GitHub Security Advisory for CVE-2026-5127

GHSA-jc25-ggg4-hhvw · Severity: high — The User Frontend: AI Powered Frontend Posting, User Directory, Profile, Membership & User...

Affected software / configurations for CVE-2026-5127

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-5127

URL Tags
https://plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.2.10/includes/Ajax/Frontend_Form_Ajax.php#L35
https://plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.2.10/includes/Ajax/Frontend_Form_Ajax.php#L36
https://plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.2.10/includes/Traits/FieldableTrait.php#L429
https://plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.2.10/includes/Traits/FieldableTrait.php#L502
https://plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.2.10/includes/Traits/FieldableTrait.php#L679
https://plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.2.10/includes/Traits/FieldableTrait.php#L704
https://plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.2.10/wpuf-functions.php#L1103
https://plugins.trac.wordpress.org/browser/wp-user-frontend/tags/4.2.10/wpuf-functions.php#L959
https://plugins.trac.wordpress.org/browser/wp-user-frontend/trunk/includes/Ajax/Frontend_Form_Ajax.php#L35
https://plugins.trac.wordpress.org/browser/wp-user-frontend/trunk/includes/Ajax/Frontend_Form_Ajax.php#L36
https://plugins.trac.wordpress.org/browser/wp-user-frontend/trunk/includes/Traits/FieldableTrait.php#L429
https://plugins.trac.wordpress.org/browser/wp-user-frontend/trunk/includes/Traits/FieldableTrait.php#L502
https://plugins.trac.wordpress.org/browser/wp-user-frontend/trunk/includes/Traits/FieldableTrait.php#L679
https://plugins.trac.wordpress.org/browser/wp-user-frontend/trunk/includes/Traits/FieldableTrait.php#L704
https://plugins.trac.wordpress.org/browser/wp-user-frontend/trunk/wpuf-functions.php#L1103
https://plugins.trac.wordpress.org/browser/wp-user-frontend/trunk/wpuf-functions.php#L959
https://plugins.trac.wordpress.org/changeset/3514258/wp-user-frontend/trunk/includes/Traits/FieldableTrait.php
https://plugins.trac.wordpress.org/changeset?old_path=%2Fwp-user-frontend/tags/4.3.1&new_path=%2Fwp-user-frontend/tags/4.3.2
https://www.wordfence.com/threat-intel/vulnerabilities/id/2b5d27cc-c6eb-4c5c-8ee1-30483b91c6fd?source=cve
cvelogic Threat Intelligence