Cross-Site Request Forgery Vulnerability in User Sync Plugin for WordPress
CVE-2025-9891

4.3MEDIUM

Key Information:

Vendor

WordPress
Status
User Sync
Vendor
CVE Published:
17 September 2025

What is CVE-2025-9891?

The User Sync plugin for WordPress is susceptible to a Cross-Site Request Forgery (CSRF) due to inadequate or missing nonce validation in the mo_user_sync_form_handler() function. This weakness allows unauthenticated attackers to exploit the vulnerability by crafting a malicious request that can deactivate the plugin, provided they can trick an administrator into executing the request through methods such as clicking on a deceptive link. This poses a significant risk to WordPress sites using the affected versions of the plugin.

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Affected Version(s)

User Sync * <= 1.0.2

References

https://www.wordfence.com/threat-intel/vulnerabilities/id...
https://plugins.trac.wordpress.org/browser/user-sync/tags...
https://plugins.trac.wordpress.org/changeset?sfp_email=&s...

CVSS V3.1

Score:
4.3
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Jonas Benjamin Friedli
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