User Registration & Membership: Privilege escalation via coupon payment bypass
Summary
The User Registration & Membership WordPress plugin before 5.3.2 does not check whether a discount coupon is valid for the selected paid membership plan. An unauthenticated attacker can place a fully discounted order that is treated as paid and is granted the role mapped to that plan without paying. If a plan is mapped to an administrator or other privileged role, this leads to privilege escalation up to administrator. Exploitation requires a site with a paid plan, a 100% discount coupon path and a privileged role mapping.
Affected
- Versions 5.2.8 to before 5.3.2 (per the CVE record; the upper bound 5.3.1 is also stated by VulDB)
- Versions before 5.2.8: Unknown.
Fixed in
- Version 5.3.2 (per the CVE record). The changelog entry and PR #1573 should be checked against this version.
Workaround
- No vendor-confirmed interim mitigation is known.
- Suggested by the research (not from a source): review membership plans mapped to privileged roles, check for 100% discount coupons, and audit recent role changes and new administrator accounts until the update is applied.
Exploitation
- No evidence of exploitation in the wild. The CVE is not listed in CISA KEV.
- Public proof of concept: Unknown.
- CISA SSVC: exploitation none, not automatable, total technical impact.
- EPSS: 0.00000 (VulDB).
Our recommendation
- Update User Registration & Membership to version 5.3.2 or later as a priority on every site with paid memberships.
- Review paid plans and their role mappings, and check whether coupons were abused.
- Check for unexpected administrator or elevated-role accounts, since exploitation may have happened without public evidence.
- Monitor user role changes after the update.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- CVE record (CVE Program) www.cve.org
- WPScan vulnerability entry wpscan.com
- OpenCVE entry app.opencve.io
- VulDB entry vuldb.com
- Fix pull request #1573 github.com
- WordPress.org plugin page wordpress.org
- WPScan plugin page wpscan.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, 13:27.
Original description (NVD)
The User Registration & Membership WordPress plugin before 5.3.2 does not verify that a discount coupon applied to a paid membership plan is actually valid for that plan before treating a fully discounted order as paid, allowing unauthenticated users to be granted the role mapped to a paid plan without paying for it, which can lead to privilege escalation up to administrator where a plan is mapped to a privileged role.
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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