wpinsider-1 Simple Membership Plugin up to 4.8.0 on WordPress Registration Flow improper authentication

Summaryinfo

A vulnerability categorized as problematic has been discovered in wpinsider-1 Simple Membership Plugin up to 4.8.0. The impacted element is an unknown function of the component Registration Flow. Such manipulation leads to improper authentication. This vulnerability is referenced as CVE-2026-77194. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability was found in wpinsider-1 Simple Membership Plugin up to 4.8.0 and classified as problematic. Affected by this issue is an unknown functionality of the component Registration Flow. The manipulation with an unknown input leads to a improper authentication vulnerability. Using CWE to declare the problem leads to CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. Impacted is integrity. CVE summarizes:

The Simple Membership plugin for WordPress is vulnerable to Authentication Bypass leading to Administrator Account Takeover in versions up to, and including, 4.8.0. This is due to improper identity verification during the public registration flow in WordPress Multisite environments, where the plugin binds new Simple Membership records to existing global WordPress users based solely on matching username and email, without requiring password verification or ownership proof, and fails to properly detect Administrator roles on child sites. This makes it possible for unauthenticated attackers to take over Administrator accounts on child sites in a Multisite network by registering a Simple Membership account with a victim's credentials on a site where public registration is enabled, then updating the victim's global WordPress password through the profile edit functionality. The vulnerability was partially patched in version 4.8.1.

The advisory is shared for download at wordfence.com. This vulnerability is handled as CVE-2026-77194 since 08/20/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version 4.8.1 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• WordPress Plugin

Vendor

• wpinsider-1

Name

• Simple Membership Plugin

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8.0

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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Once again VulDB remains the best source for vulnerability data.

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