Medium severity · published Jul 22, 2025
CVE-2025-6831
User Registration <= 4.2.4 - Authenticated (Contributor+) Stored Cross-Site Scripting via urcr_restrict Shortcode
6.4
CVSS
0.4%
EPSS
No
On KEV
Description
The User Registration plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's urcr_restrict shortcode in all versions up to, and including, 4.2.4 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 30% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
Affected product
UR
User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder
wpeverest
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-6831
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-6831
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/user-registration/tags/4.2.4/modules/content-restriction/class-urcr-shortcodes.php
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/user-registration/tags/4.2.4/modules/content-restriction/class-urcr-shortcodes.php#L147
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/changeset/3329704/
wordpress.org
https://wordpress.org/plugins/user-registration/#developers
www.wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/50f3e469-f788-45da-95e7-aa6da1e87fd1?source=cve
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