● Medium · CVSS 5.3

How to Fix CVE-2026-6145: Missing Authorization in User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder

Q: Is CVE-2026-6145 being exploited in the wild?

Public exploitation has not been confirmed by CISA at the time of writing. Treat the patch as time-sensitive anyway; reports often lag actual abuse.

Q: Will a WAF or IDS rule fully mitigate CVE-2026-6145?

No. Network-layer filters can reduce noise and slow opportunistic scanners, but they will not stop a determined attacker. The vendor patch is the only durable fix.

Q: How long should I plan for the upgrade?

Typical vendor-documented upgrade windows for User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder run from a few minutes to under an hour depending on cluster size. Test in a staging environment first and follow the vendor's documented HA upgrade order.

Other vulnerabilities in the same area that are worth patching alongside this one:

How to Fix CVE-2026-1410: Authentication Bypass in 777VR1 — Authentication Bypass in 777VR1
How to Fix CVE-2026-4060: CWE-89 Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') — CWE-89 Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
How to Fix CVE-2026-7258: Out-of-bounds Read in PHP , Out-of-bounds Read in PHP
How to Fix CVE-2026-22604: Information Disclosure in openproject , Information Disclosure in openproject
How to Fix CVE-2026-2530: Command Injection in WL-WN579A3 , Command Injection in WL-WN579A3

*By Sai Kiran Pandrala*

⚡ At a glance


Severity	CVSS 5.3 - Medium
Actively exploited?	Not currently listed in CISA KEV
Affected	0 <= 5.1.5
Fixed in	See vendor advisory
Type (CWE)	CWE-862: Missing Authorization

What is CVE-2026-6145?

CVE-2026-6145 is a missing-authorization flaw in User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder. A sensitive endpoint or action is reachable without the capability or role check it should require, letting a low-privileged or unauthenticated caller perform actions reserved for administrators. Vendor description: The User Registration & Membership plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 5.1.5. This is due to the is_admin_creation_process() method relying solely on the presence of action=createuser in the $_REQUEST superglobal without performing any authentication or capability check.

Why this CVE matters

Missing-authorization bugs in plugins and management products are the single most common WordPress-plugin vulnerability class in 2026. Most weaponized exploits chain a missing capability check with another action that grants administrator access.

For deployments of User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder that have been exposed to the public internet during the disclosure window, the operating assumption should be that scanning has already happened. Even where exploitation has not been publicly observed, scanning for the vulnerable fingerprint is cheap and routine. Patching closes the door; log review and credential rotation close out the rest of the response.

Am I affected?

You are affected if your installation matches any of these version ranges:

User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder: 0 <= 5.1.5

Check your installed version against the list above. If you cannot determine the version, treat the system as affected and follow the upgrade path below.

Open User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder's About dialog or run the vendor-documented version-check command. Compare the result against the affected ranges in the advisory.

How to fix CVE-2026-6145

Read the vendor advisory in full: https://www.wordfence.com/threat-intel/vulnerabilities/id/b6b349f2-24c9-4921-bb5f-a7726ebc5c2a?source=cve
Upgrade User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder to the patched build listed in the vendor advisory.
Back up the configuration (and database, where applicable) before upgrading.
Apply the patch in a maintenance window. For HA pairs, upgrade the standby node first, fail over, then upgrade the former primary.
Restart the affected service so the patched binary loads, then verify the new version (see verification section).

WordPress upgrade (WP-CLI)

The vendor advisory (https://www.wordfence.com/threat-intel/vulnerabilities/id/b6b349f2-24c9-4921-bb5f-a7726ebc5c2a?source=cve) names the patched release as the build named in the vendor advisory (https://www.wordfence.com/threat-intel/vulnerabilities/id/b6b349f2-24c9-4921-bb5f-a7726ebc5c2a?source=cve).


# 1. Snapshot the database and wp-content directory
wp db export wp-backup-$(date +%F).sql
tar -czf wp-files-$(date +%F).tgz /var/www/html/wp-content

# 2. Upgrade core (or the affected plugin) to the patched version
wp core update
wp core update-db
wp plugin update --all

# 3. Verify
wp core version
wp plugin list --status=active --field=name,version

Linux package upgrade

The vendor advisory (https://www.wordfence.com/threat-intel/vulnerabilities/id/b6b349f2-24c9-4921-bb5f-a7726ebc5c2a?source=cve) names the patched build as the build named in the vendor advisory (https://www.wordfence.com/threat-intel/vulnerabilities/id/b6b349f2-24c9-4921-bb5f-a7726ebc5c2a?source=cve).


# Ubuntu / Debian
sudo apt-get update
sudo apt-get install --only-upgrade userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder
dpkg -s userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder | grep -i version

# RHEL / Rocky / AlmaLinux / Fedora
sudo dnf upgrade --refresh userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder -y
rpm -q userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder

# openSUSE
sudo zypper refresh && sudo zypper update userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder

# Restart the service that loads the patched binary
sudo systemctl restart userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder 2>/dev/null || true
sudo systemctl status userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder --no-pager 2>/dev/null || true


# Vendor advisory: https://www.wordfence.com/threat-intel/vulnerabilities/id/b6b349f2-24c9-4921-bb5f-a7726ebc5c2a?source=cve
# Container deployments: rebuild with the patched package layer, then roll the workload.
docker pull <your-registry>/userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder:<patched-tag>
docker stop <app> && docker rm <app>
docker run -d --name <app> <your-registry>/userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder:<patched-tag>

# Kubernetes
kubectl set image deployment/<deployment-name> userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder=<your-registry>/userregistrationmembershipfreepaidmembershipssubscriptionscontentrestrictionuserprofilecustomuserregistrationloginbuilder:<patched-tag>
kubectl rollout status deployment/<deployment-name>

Verify the fix landed


# Vendor advisory: https://www.wordfence.com/threat-intel/vulnerabilities/id/b6b349f2-24c9-4921-bb5f-a7726ebc5c2a?source=cve
# 1. Compare the running version against the fixed build named above.
#    (Replace the version probe with the platform-specific command from the block above.)

# 2. Re-scan with your vulnerability scanner (Nessus, Qualys, Tenable, OpenVAS).
#    The scanner should no longer flag this CVE on the patched target.

# 3. Inspect recent service / kernel logs for crash loops or rollback events.
journalctl -u <service> --since "10 minutes ago"
dmesg --since "10 minutes ago"

If you cannot patch immediately

Restrict access to the affected endpoint at a reverse proxy or WAF so that only trusted authenticated users can reach it. Apply the vendor patch as the durable fix; capability checks belong in the application code.

How to verify the fix worked

After applying the patch, verify the running version in the product's admin UI or via the vendor-documented CLI command.
Confirm the patched build matches the version listed in the vendor advisory.
Run an authenticated vulnerability scan with a current signature set and confirm the scanner no longer flags CVE-2026-6145.
Review logs for the entire pre-patch window for indicators of compromise listed in the vendor or CISA advisory.
Confirm any network-layer mitigations that were applied as a stopgap have been reverted (or left in place intentionally) once the patch is verified.

If your installation was internet-reachable during the disclosure window, treat log review as part of the remediation rather than an optional follow-up. Look for log entries that do not match your normal request patterns, especially repeated requests to the same uncommon endpoint, and any administrative changes you cannot tie back to a known operator.

Frequently asked questions

Is CVE-2026-6145 being exploited in the wild?