CVE-2025-1564: SetSail Membership Auth Bypass Vulnerability

CVE-2025-1564 Overview

CVE-2025-1564 is an authentication bypass vulnerability affecting the SetSail Membership plugin for WordPress. The flaw exists in all versions up to and including 1.0.3. The plugin fails to properly verify a user's identity during the social login flow. Unauthenticated attackers can exploit this weakness to log in as any registered user, including administrators. Successful exploitation results in full account takeover and complete site compromise. The vulnerability is classified under CWE-288: Authentication Bypass Using an Alternate Path or Channel.

Critical Impact

Unauthenticated attackers can assume the identity of any WordPress user, including administrators, resulting in full site takeover without credentials or user interaction.

Affected Products

• SetSail Membership plugin for WordPress, all versions up to and including 1.0.3
• WordPress sites using the SetSail travel agency theme with the bundled membership plugin
• Sites with social login functionality enabled through the plugin

Discovery Timeline

• 2025-03-01 - CVE-2025-1564 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2025-1564

Vulnerability Analysis

The SetSail Membership plugin exposes a social login handler that authenticates users without sufficiently validating identity assertions from the social provider. An attacker can supply a target user identifier — such as an email address or social account ID belonging to a legitimate administrator — and the plugin issues a valid authenticated session for that account. No password, token, or cryptographic proof of ownership is required.

This class of flaw maps directly to [CWE-288], where an alternate authentication channel bypasses the primary credential check. Because the network attack vector requires no privileges and no user interaction, an attacker can automate large-scale account takeovers against vulnerable WordPress installations.

The Exploit Prediction Scoring System reports a probability of 0.191% for this CVE, but real-world risk is elevated due to the public Wordfence advisory and the trivial nature of exploitation.

Root Cause

The root cause is missing verification of the identity returned by the social login provider. The plugin trusts a client-supplied user identifier instead of validating a signed token or callback from the identity provider against the expected user record. This breaks the trust boundary between the authentication broker and the application.

Attack Vector

The attack is delivered remotely over HTTP or HTTPS against the WordPress site. An unauthenticated attacker crafts a request to the plugin's social login endpoint and supplies the identifier of a target account. The server responds by establishing an authenticated session as the targeted user. Administrator accounts are the highest-value targets because login as admin grants plugin installation, file editing, and database access.

The SetSail Membership plugin does not validate the authenticity
of the identity asserted during social login. An attacker submits
a request to the plugin's login handler with an attacker-controlled
user identifier, and the application establishes a session for
that user without verifying any cryptographic proof of ownership.
No verified proof-of-concept code is published; refer to the
Wordfence advisory for additional technical context.

Detection Methods for CVE-2025-1564

Indicators of Compromise

• Unexpected administrator logins from IP addresses or geolocations not associated with known administrators
• New administrator accounts, modified user roles, or password resets occurring without a corresponding helpdesk ticket
• Plugin or theme files modified shortly after a successful login from the social login endpoint
• WordPress audit log entries showing repeated requests to the SetSail Membership social login handler

Detection Strategies

• Inspect web server access logs for repeated POST requests to the plugin's social login endpoint, especially from a single IP targeting multiple usernames
• Correlate WordPress wp_login events with the originating authentication path to identify sessions established without a corresponding social provider callback
• Alert on privilege changes, new admin user creation, or installation of unfamiliar plugins following any social login event

Monitoring Recommendations

• Forward WordPress authentication and audit logs to a central SIEM or data lake for correlation against IP reputation and behavioral baselines
• Monitor file integrity for wp-content/plugins, wp-content/themes, and wp-config.php to detect post-compromise tampering
• Track outbound connections from the web host that could indicate webshell beaconing or data exfiltration after account takeover

How to Mitigate CVE-2025-1564

Immediate Actions Required

• Disable or uninstall the SetSail Membership plugin until a patched version is released by the vendor
• Force a password reset for all administrator and privileged accounts, and invalidate active sessions
• Audit the WordPress user table for unauthorized accounts or role escalations and remove any unexpected administrators
• Review installed plugins, themes, and the mu-plugins directory for unauthorized code introduced after the vulnerability window

Patch Information

At the time of NVD publication, all versions of the SetSail Membership plugin up to and including 1.0.3 are affected. Administrators should consult the Wordfence Vulnerability Report and the ThemeForest SetSail product page for vendor updates and apply any released patch immediately upon availability.

Workarounds

• Deactivate the SetSail Membership plugin in the WordPress admin console to remove the vulnerable endpoint
• Block requests to the plugin's social login handler at the web application firewall or reverse proxy layer
• Restrict access to /wp-admin by IP allowlist while the vulnerability remains unpatched
• Enforce multi-factor authentication for administrator accounts through a separate, trusted plugin to reduce takeover impact

# Disable the vulnerable plugin via WP-CLI
wp plugin deactivate setsail-membership
wp plugin delete setsail-membership

# Force logout of all users to invalidate sessions
wp user session destroy --all

# List administrator accounts for review
wp user list --role=administrator --fields=ID,user_login,user_email,user_registered