Summaryinfo

A vulnerability described as critical has been identified in Membership Plugin up to 3.2.18/3.2.20 on WordPress. This affects the function rcp_setup_registration_init of the component POST Parameter Handler. Such manipulation of the argument rcp_level leads to Remote Code Execution. This vulnerability is listed as CVE-2026-1321. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Membership Plugin up to 3.2.18/3.2.20 on WordPress. Affected by this issue is the function rcp_setup_registration_init of the component POST Parameter Handler. The manipulation of the argument rcp_level with an unknown input leads to a remote code execution vulnerability. Using CWE to declare the problem leads to CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality, integrity, and availability. CVE summarizes:

The Membership Plugin – Restrict Content plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 3.2.20. This is due to the `rcp_setup_registration_init()` function accepting any membership level ID via the `rcp_level` POST parameter without validating that the level is active or that payment is required. Combined with the `add_user_role()` method which assigns the WordPress role configured on the membership level without status checks, this makes it possible for unauthenticated attackers to register with any membership level, including inactive levels that grant privileged WordPress roles such as Administrator, or paid levels that charge a sign-up fee. The vulnerability was partially patched in version 3.2.18.

The advisory is available at wordfence.com. This vulnerability is handled as CVE-2026-1321. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 03/05/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-9796). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• WordPress Plugin

Name

• Membership Plugin

Version

• 3.2.0
• 3.2.1
• 3.2.2
• 3.2.3
• 3.2.4
• 3.2.5
• 3.2.6
• 3.2.7
• 3.2.8
• 3.2.9
• 3.2.10
• 3.2.11
• 3.2.12
• 3.2.13
• 3.2.14
• 3.2.15
• 3.2.16
• 3.2.17
• 3.2.18
• 3.2.19
• 3.2.20

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CPE 2.2info

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