WordPress security changelog
HIGH CVE-2026-97337 Deferred

Simple Membership: Activation email redirection and credential disclosure

The Simple Membership plugin for WordPress is vulnerable to unauthorized modification of data and sensitive information disclosure in versions up to, and including, 4.8.3 via the resend-activation and email-activation endpoints. The endpoints are dispatched from SwpmInitTimeTasks::check_and_do_email_activation() on frontend init with no authentication, nonce, capability, or ownership check, and the recipient address used by SwpmRegistration::send_reg_email() is taken from an attacker-controlled $_POST['email'] parameter (overriding the member's registered address). This makes it possible for unauthenticated attackers to redirect an arbitrary pending member's activation email — and the follow-up 'registration complete' email containing the member's username and plaintext password — to an attacker-chosen address, and to then activate that member's account without their consent. The official changelog confirms the fixed release as 4.8.4.

CVE / CNA score 7.5 CVSS 3.1 · security@wordfence.com
NVD score Pending NVD has not published its own CVSS assessment.
Component
Simple Membership
Plugin slug
simple-membership
Affected
<= 4.8.3
Safe version
4.8.4
Published
Oct 03, 2026
Weakness
CWE-862 — Missing Authorization

This CVE was published Oct 03, 2026 and is one of 35 known issues for this plugin.

Update, patch or deactivate.

Update Simple Membership to 4.8.4 or a later supported release. An application-level fix should bind activation messages to the member’s saved address, validate single-use expiring activation tokens, and never include plaintext passwords in email. Reset credentials for accounts whose activation emails may have been redirected.

A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Technical description

The Simple Membership plugin for WordPress is vulnerable to unauthorized modification of data and sensitive information disclosure in versions up to, and including, 4.8.3 via the resend-activation and email-activation endpoints. The endpoints are dispatched from SwpmInitTimeTasks::check_and_do_email_activation() on frontend init with no authentication, nonce, capability, or ownership check, and the recipient address used by SwpmRegistration::send_reg_email() is taken from an attacker-controlled $_POST['email'] parameter (overriding the member's registered address). This makes it possible for unauthenticated attackers to redirect an arbitrary pending member's activation email — and the follow-up 'registration complete' email containing the member's username and plaintext password — to an attacker-chosen address, and to then activate that member's account without their consent.

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

Primary and upstream sources