CVE-2026-18345: WP User Manager: Unauthorized modification of data

WP User Manager: Unauthorized modification of data

The WP User Manager plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the Connect::complete() function in versions up to, and including, 2.9.18. The function is registered on the admin_init hook (which fires for every authenticated user that reaches /wp-admin/, including Subscribers) and performs no current_user_can() or nonce verification before fetching Stripe credentials from the external WPUM connect service and writing them (publishable key, secret key, gateway mode, and connected Stripe account ID) into the wpum_settings option via wpum_update_option()/update_option(). This makes it possible for authenticated attackers, with Subscriber-level access and above, to hijack the site's Stripe integration by completing their own Stripe Connect OAuth flow and then invoking the callback on the target site, causing all subsequent Stripe payments to be routed to the attacker's Stripe account.

Description from the National Vulnerability Database, published by Wordfence

What it means for a small business

WP User Manager is a WordPress plugin. If your website uses it, the flaw is on your site whether or not anyone has noticed yet: attackers scan the whole internet for the plugins with published flaws, usually within days of a record like this one going public.

Most small-business sites run 15 to 40 plugins, and few owners know the list. You can check from WordPress itself (Plugins, then Installed Plugins), or let our free plugin check look it up by name.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.34%, higher than 26% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 28, 2026, updated daily.

Check your own setup

Is WP User Manager safe? Every recorded flaw in it, the version that fixes each, and whether it’s still maintained.
Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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