Broken Access Control in RegistrationMagic (<= 6.0.7.4) — What WordPress Site Owners Must Do Now

Published: 28 Jan, 2026   |   CVE: CVE-2026-1054   |   Affected versions: RegistrationMagic <= 6.0.7.4   |   Fixed in: 6.0.7.5   |   Severity: Low (CVSS 5.3)

As a Hong Kong-based security consultant who works on WordPress incidents across APAC, I treat plugin access-control flaws seriously even when their CVSS appears “low.” Broken authorization can be a quiet enabler for follow-on attacks. This advisory explains what the RegistrationMagic vulnerability is, how attackers may leverage it, how to check your environment, and practical, prioritised steps you should take right now.

Quick summary for busy site owners

• What happened: An unauthenticated endpoint in RegistrationMagic allowed modification of plugin settings without proper authorization or nonce checks.
• Who’s impacted: Sites running RegistrationMagic version 6.0.7.4 or earlier.
• Immediate action: Update RegistrationMagic to 6.0.7.5 (or later) as soon as possible. If you cannot update immediately, apply temporary mitigations (see below) and monitor logs closely.
• Extra checks: Inspect plugin settings in the database, review access logs for suspicious requests, and confirm there are no unexpected admin users or changed notification emails.

Why broken access control matters

Broken access control describes missing or bypassable authorization logic. If settings that should be restricted can be changed by unauthenticated users, attackers may:

• Enable registration flows that create privileged accounts or bypass verification.
• Change redirect URLs to route users to phishing pages.
• Disable logging or protections.
• Set options that open other features exploitable later.

When combined with weak admin passwords, exposed admin pages, or other vulnerabilities, even a “low” severity bug can escalate into a complete site compromise.

Technical overview — how an attack might look (high level)

I will not publish exploit code. Below is a high-level attack sequence to help defenders recognise indicators.

1. Scan for sites with RegistrationMagic installed and probe publicly accessible plugin endpoints (admin-ajax actions, REST endpoints, or custom form handlers).
2. Find an endpoint that accepts POST/GET to modify settings but does not verify requester authentication or capability.
3. Craft and submit a request with changed configuration values (redirects, notification emails, toggles).
4. Server accepts and persists changes in the database (wp_options or plugin tables).
5. Attacker verifies changes and uses them to create backdoor accounts, redirect admins, or prepare follow-up exploitation.

Common targets include admin-ajax.php actions, plugin admin pages that accept POSTs without nonce/capability checks, or REST endpoints with broken permission callbacks.

Indicators of compromise (IoCs) and what to look for

If you run RegistrationMagic (≤ 6.0.7.4), prioritise these checks:

1. Plugin settings tampering

• Search for unexpected values in options related to the plugin (redirect URLs, admin notification email, integration keys, toggles enabling admin-like features).
• Examples — adjust option names to your environment:

wp option get registrationmagic_settings
wp option get registrationmagic_options

SELECT option_name, option_value
FROM wp_options
WHERE option_name LIKE '%registrationmagic%'
ORDER BY option_name;

2. Unexpected admin users or user metadata changes

• List administrator users:

wp user list --role=administrator --fields=ID,user_login,user_email,display_name

• Check for recent user creation (example using current date):

wp user list --format=csv | grep "$(date +%Y-%m-%d)"

• Verify registration notification emails were not changed to attacker-controlled addresses.

3. Access logs and POST requests

• Search webserver logs for POSTs to plugin endpoints, admin-ajax actions, or parameter names related to RegistrationMagic:

grep -E "admin-ajax.php|registrationmagic|regmagic|registermagic" /var/log/nginx/access.log | grep "POST"

• Look for anomalous user agents, repeated requests from single IPs, or known malicious sources.

4. Database timestamps and changed files

• Check update timestamps that align with suspicious activity.
• Run file integrity checks to ensure no new PHP backdoors were dropped:

wp core verify-checksums
# or compare plugin/theme files with clean copies

5. Email notification changes or toggles

• Confirm the plugin’s notification email addresses remain legitimate.

If you detect suspicious activity, follow the incident response steps below.

Immediate mitigations (priority order)

1. Update the plugin to 6.0.7.5 (or later)
   This is the definitive fix. Patch in staging first, then production. Monitor logs during and after the update.
2. If you cannot update immediately — apply temporary virtual patching or blocking rules
   Deploy temporary rules at the edge (WAF, reverse proxy, or webserver) to block unauthenticated attempts to modify RegistrationMagic settings. Useful patterns to block:
   • POSTs to admin-ajax.php where the action parameter matches setting-update actions.
   • POSTs to plugin-specific endpoints such as /wp-content/plugins/registrationmagic/… that indicate admin/settings actions.
   • Requests attempting to set option names or suspicious parameter names.

   Example ModSecurity-style rule (adapt to your environment):

   # Block attempts to update registration plugin settings via admin-ajax.php
   SecRule REQUEST_URI "@contains admin-ajax.php" \
     "phase:2,chain,deny,log,status:403,msg:'Blocked attempt to modify registration plugin settings (virtual patch)',id:1000011"
   SecRule ARGS_NAMES|ARGS "@rx ^(registrationmagic|regmagic|reg_magic).*(settings|option|update|save)$" \
     "t:none"

   Example nginx location-based blocking:

   location ~* /wp-admin/admin-ajax.php {
     if ($request_method = POST) {
       if ($arg_action ~* "(registra|registration|regmagic).*(update|save|settings)") {
         return 403;
       }
     }
     proxy_pass ...;
   }

   Validate rules carefully to avoid breaking legitimate features.

3. Rate-limit and throttle
   Apply rate limiting for POST requests to admin-ajax and plugin endpoints to reduce automated exploitation attempts. Example (nginx limit_req):

   limit_req_zone $binary_remote_addr zone=ajax:10m rate=5r/m;
   location = /wp-admin/admin-ajax.php {
       limit_req zone=ajax burst=10 nodelay;
       proxy_pass ...;
   }

4. Temporary access restrictions
   If registration is not required, disable it temporarily or block plugin endpoints via .htaccess/nginx until the patch is applied.
5. Harden admin area
   Restrict wp-admin and wp-login.php to trusted IPs where practical. Enforce strong admin passwords and two-factor authentication.
6. Scan and monitor
   Run a full malware scan and monitor requests to plugin endpoints for recurring patterns.

Practical WAF rule examples and guidance

Below are illustrative examples. Test on staging first and tune to your site.

SecRule REQUEST_METHOD "POST" "chain,phase:2,deny,log,status:403,id:1000100,msg:'Block: Unauthenticated plugin settings write attempt'"
SecRule REQUEST_URI|ARGS_NAMES "@rx (admin-ajax\.php|registrationmagic|regmagic|save_settings|update_settings|rm_save|rm_update)" "t:none"

SecRule REQUEST_METHOD "POST" "chain,phase:2,deny,log,status:403,id:1000101,msg:'Block unauthenticated POST to plugin admin endpoints'"
SecRule REQUEST_URI "@rx /wp-content/plugins/registrationmagic/.*(admin|ajax|settings).*" "t:none"
SecRule &REQUEST_HEADERS:Cookie "@eq 0" "t:none"

location ~* /wp-content/plugins/registrationmagic/.*(admin|ajax|settings).* {
    if ($http_cookie !~* "wordpress_logged_in_") {
        return 403;
    }
    proxy_pass ...;
}

Generic blocking may break legitimate functionality. Be conservative and test rules thoroughly.

Detection queries and audit steps (hands-on)

1. Search for options referencing registration or plugin settings:

   SELECT option_name, LENGTH(option_value) AS val_length, LEFT(option_value,200) as preview
   FROM wp_options
   WHERE option_name LIKE '%registration%'
   OR option_name LIKE '%regmagic%'
   ORDER BY option_id DESC LIMIT 200;

2. Dump plugin options via WP‑CLI:

   wp db query "SELECT option_name, option_value FROM wp_options WHERE option_name LIKE '%registrationmagic%';"

3. Search access logs for suspicious POSTs:

   grep -i "admin-ajax.php" /var/log/nginx/access.log | grep POST | egrep -i "registrationmagic|regmagic|action=" | tail -n 200

4. Identify recent filesystem changes:

   find /var/www/html/wp-content -type f -mtime -7 -ls | sort -k7 -r

5. Check scheduled events (attacker may schedule tasks):

   wp cron event list --fields=hook,next_run

6. Review PHP and webserver error logs around suspicious request windows.

If you were compromised — step-by-step incident response

1. Isolate: If exploitation is ongoing, consider blocking traffic or switching to maintenance mode while investigating.
2. Snapshot: Take a full backup (files + DB) immediately for forensics and store offline.
3. Identify scope: Use the detection queries above. Check for new admin accounts, modified options, changed files, and scheduled tasks.
4. Contain and remove: Revoke suspicious users, revert plugin settings from known-good backups, disable the plugin if needed, and remove discovered backdoors.
5. Patch: Update RegistrationMagic to 6.0.7.5 or later, and update WordPress core, themes, and other plugins.
6. Rotate secrets: Change administrator passwords and API keys. Rotate WordPress salts/keys in wp-config.php and force logout of all sessions:

   wp user session destroy --all

7. Restore and verify: If restoring from backup, ensure the backup predates the compromise and re-scan after restore.
8. Monitor and report: Maintain elevated monitoring for at least 30 days and inform stakeholders according to your disclosure policy.

Developer guidance — how to fix this class of problem

If you are a plugin author or developer, follow these rules to avoid broken access control:

1. Authorization checks: For AJAX actions, ensure capability checks:

   add_action('wp_ajax_myplugin_update_settings', 'myplugin_update_settings_callback');
   
   function myplugin_update_settings_callback() {
       if ( ! current_user_can( 'manage_options' ) ) {
           wp_send_json_error( 'Unauthorized', 403 );
       }
       // Process settings...
   }

2. Nonce verification: Use nonces for state-changing operations:

   check_ajax_referer( 'myplugin_save_settings', 'security' );

3. REST API permission callbacks: Always supply a robust permission_callback:

   register_rest_route( 'myplugin/v1', '/settings', array(
       'methods' => 'POST',
       'callback' => 'myplugin_save_settings',
       'permission_callback' => function () {
           return current_user_can( 'manage_options' );
       },
   ));

4. Input validation and sanitization: Use WordPress sanitization functions (sanitize_text_field, sanitize_email, etc.) and never write POST data blindly to the DB.
5. Principle of least privilege: Limit what settings can be changed and restrict sensitive changes to trusted roles.
6. Logging and audit trail: Log administrative changes (who, what, when) to support incident response.

Long-term hardening checklist

• Keep WordPress core, plugins, and themes up to date.
• Minimise plugin usage — remove unused plugins to reduce attack surface.
• Enforce 2FA and strong password policies for administrators.
• Restrict admin interfaces to trusted IPs where practical.
• Regularly backup and test restore procedures.
• Monitor logs and set alerts for anomalous POST requests, unknown admin creation, or mass option changes.
• Implement file integrity monitoring and scheduled malware scans.

How layered defences help

Layered defences reduce exposure while you patch:

• Virtual patching (edge/host rules) can block exploit attempts temporarily.
• Edge rate-limiting and bot mitigation reduce automated scanning and exploitation attempts.
• Automated scanning and file integrity checks help detect changes early.
• Incident response support from experienced consultants can accelerate containment and remediation.

Recommended remediation timeline (24–72 hours)

• Within 1 hour: Identify all installations running RegistrationMagic and prioritise by traffic/criticality. If you can’t patch immediately, apply temporary blocking at the edge.
• Within 6–12 hours: Update RegistrationMagic to 6.0.7.5 in staging and test registration/admin workflows. Push to production in a maintenance window.
• Within 24–72 hours: Complete a site-wide scan for IoCs. Rotate admin credentials and keys if suspicious activity was observed. Harden admin access and enable continuous monitoring.

Frequently asked questions

Q: My site doesn’t use public registrations — am I still at risk?

A: Possibly. Vulnerable code paths may still be reachable via plugin endpoints. Verify whether the plugin’s admin endpoints are accessible and apply temporary blocking until patched.

Q: Will disabling RegistrationMagic remove the risk?

A: Disabling the plugin usually stops the vulnerable code from executing. However, if an attacker already modified settings or created backdoor accounts, disabling alone is insufficient. Follow the detection checklist and remediate discovered changes.

Q: Will WAF rules break legitimate traffic?

A: Poorly tuned rules can cause false positives. Test on staging, use monitoring-only modes where available, and roll out conservative rule sets first.

Final checklist — what to do right now

1. Identify all WordPress sites using RegistrationMagic (≤ 6.0.7.4).
2. Update RegistrationMagic to 6.0.7.5 as soon as possible.
3. If unable to update immediately, apply temporary edge or server-level rules to block unauthenticated setting changes.
4. Search for indicators of compromise: changed options, new admin accounts, suspicious POSTs in logs.
5. Run a full scan and review file integrity.
6. Rotate admin passwords and keys if suspicious activity is detected.
7. Enable two-factor authentication for all administrators.
8. If required, engage a qualified security consultant to triage logs, create precise mitigation rules, and guide remediation.

If you need help: engage an experienced WordPress security professional or incident response consultant. They can analyse logs, craft emergency edge rules tuned to your stack, and assist with clean remediation.

Stay calm and methodical: detect, contain, eradicate, patch, and monitor. That sequence limits damage and prevents “low” issues from becoming high-impact incidents.