CVE-2026-18547 Cross-site scripting in Ultimate Member – User Profile, Registration, Login, Member Directory, Content Restriction & Membership Plugin
Authenticated attackers can inject arbitrary scripts via profile fields, leading to code execution when other users view the profile.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-18547?
CVE-2026-18547 is a medium-severity cross-site scripting vulnerability in ultimatemember Ultimate Member – User Profile, Registration, Login, Member Directory, Content Restriction & Membership Plugin, published on 25 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
The Ultimate Member – User Profile, Registration, Login, Member Directory, Content Restriction & Membership Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Textarea Profile Field with HTML Support (DOM Gadget via id Attribute) in all versions up to, and including, 2.12.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This is possible because the wp_kses 'templates' allowlist permits the id attribute on div elements but does not neutralize unescaped quotes within its value; when pickadate.js concatenates the stored id value into an HTML string via jQuery .html() on profile page load, the smuggled onfocus and autofocus attribute syntax breaks out of attribute context and executes as JavaScript.
Weakness: CWE-79
Which versions are affected by CVE-2026-18547?
How do I fix CVE-2026-18547?
No fix has been published for CVE-2026-18547 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-18547 being exploited?
There is no known exploitation of CVE-2026-18547 in the wild and no public exploit code.
Sources
Also known as GHSA-rhh6-vxq9-rqm4.