7.5

CVE-2026-86406: unknown user registration & membership Improper Privilege Management

CVSS: 7.5v3.1HighDeferred
Published 13-09-2026Last modified 13-09-2026
Open JSON

Vulnerability summary

CVE-2026-86406 is a high (CVSS 7.5) Improper Privilege Management vulnerability in unknown user registration & membership. EPSS estimates a 0.32% chance of exploitation in the next 30 days, higher than 23.7% of scored vulnerabilities. 1 public exploit is recorded. Fixed in 5.2.8.

Overall risk
40/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.32%
0%100%
Low · +0.13 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference

Timeline

  1. 13-09-2026
    PublishedVulnerability first disclosed.
  2. 13-09-2026
    Last modifiedVulnerability information updated.

Description

The User Registration & Membership WordPress plugin before 5.2.8 does not check the capability of the user making a membership purchase, and does not validate the payment method or the plan submitted with it, allowing any authenticated user such as a subscriber to be granted the WordPress role attached to a paid plan without paying for it. Where the site owner has mapped a plan to a privileged role, this leads to privilege escalation up to administrator.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.32%

Chance of exploitation in the next 30 days

Percentile

24%

Versus all other CVEs

30-day change

+0.13 pp

From 0.19% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.32%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (wpscan.com)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Unknown1 product
Wordpress1 product
  • user-registration≥ 4.4.6, ≤ 5.2.7 (fixed in 5.2.8)

2 vendors · 2 products

References

2 links