User Registration & Membership WordPress plugin: Authentication bypass in payment-gated registration
Summary
The User Registration & Membership WordPress plugin before version 5.3.2 does not enforce its payment-before-login restriction when a registration is submitted without a membership selection. An unauthenticated attacker can create an account on a payment-gated registration form and log in without paying. The impact is limited to access to paid-only content or features; the CVSS vector shows no integrity or availability impact.
Affected
- User Registration & Membership (WordPress plugin) versions 0 to before 5.3.2
- Vendor: WPEverest (ThemeGrill)
Fixed in
- Fixed in version 5.3.2 (inferred from the CVE range; no separate vendor advisory found)
Workaround
Unknown.
Exploitation
- Attack requires no account and no user interaction (CVSS 5.3, AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)
- CISA SSVC: automatable yes, technical impact partial, exploitation none
- Not listed in CISA KEV
- No public proof of concept or in-the-wild exploitation found
Our recommendation
- Update User Registration & Membership to version 5.3.2 or later
- Check whether payment-gated registration forms are in use; if so, review recently created accounts for accounts that never paid
- Check whether any plan is mapped to an administrator or other privileged role
- Note that related CVEs in the same batch (CVE-2026-109870, CVE-2026-109871, CVE-2026-11964, CVE-2026-11966) are covered by the same update, so update rather than fix this issue in isolation
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- WPScan advisory wpscan.com
- CVE record CVE-2026-109873 www.cve.org
- VulDB CVE-2026-109873 vuldb.com
- WordPress.org plugin page wordpress.org
- Strix CVE-2026-109873 www.strix.ai
- WPEverest about page wpuserregistration.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 11 Nov 2026, 18:07.
Original description (NVD)
The User Registration & Membership WordPress plugin before 5.3.2 does not enforce its payment-before-login restriction when a registration is submitted without a membership selection, allowing unauthenticated users to create an account on a payment-gated registration form and log in without completing payment.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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