CVE-2025-8783 Overview
CVE-2025-8783 is a Stored Cross-Site Scripting (XSS) vulnerability in the Contact Manager plugin for WordPress. The flaw affects all versions up to and including 8.6.5. It stems from insufficient input sanitization and output escaping of the title parameter in the plugin's admin page functionality.
Authenticated attackers with administrator-level access can inject arbitrary web scripts into pages. The injected scripts execute whenever a user accesses the affected page. The vulnerability only impacts multi-site installations and installations where unfiltered_html has been disabled, limiting the practical attack surface.
Critical Impact
Authenticated administrators on multi-site WordPress installations can store malicious JavaScript that executes in the context of any user viewing the injected page.
Affected Products
- Contact Manager plugin for WordPress, all versions through 8.6.5
- WordPress multi-site installations running the vulnerable plugin
- WordPress installations with unfiltered_html capability disabled
Discovery Timeline
- 2025-08-19 - CVE-2025-8783 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-8783
Vulnerability Analysis
The vulnerability is a Stored Cross-Site Scripting flaw classified under CWE-79. The Contact Manager plugin accepts user-supplied content via the title parameter without properly sanitizing input or escaping output when the value is rendered. This allows persistent JavaScript payloads to be stored in the database and executed later in a victim's browser.
Exploitation requires administrator-level authentication, which raises the privilege barrier significantly. The scope is further restricted to multi-site deployments and configurations where the unfiltered_html capability has been removed. In standard single-site WordPress installations, administrators already possess unfiltered_html and can natively insert HTML, so the issue is not treated as a security boundary violation there.
Root Cause
The root cause lies in admin-pages-functions.php where the plugin processes the title parameter. The code path at line 524 fails to apply WordPress sanitization helpers such as wp_kses() or esc_html() on input and output. Attacker-controlled markup is persisted and later echoed into the DOM without encoding, allowing script tags and event handlers to execute.
Attack Vector
An authenticated administrator on a WordPress multi-site network submits a crafted title value containing JavaScript. The payload is stored in the database and rendered to any user who loads the affected page, including super administrators of the network. This creates a privilege-pivoting opportunity across sites in the multi-site hierarchy. See the WordPress Plugin Code Reference and the Wordfence Vulnerability Report for technical details.
Detection Methods for CVE-2025-8783
Indicators of Compromise
- Unexpected <script> tags, event handlers (onerror, onload), or encoded JavaScript stored within Contact Manager plugin records.
- Outbound HTTP requests from authenticated session browsers to attacker-controlled domains after visiting Contact Manager pages.
- New or modified administrator accounts created shortly after a user viewed an injected plugin page.
Detection Strategies
- Audit the WordPress database for Contact Manager entries containing HTML or JavaScript markup in title fields.
- Review web server access logs for POST requests to Contact Manager admin endpoints followed by suspicious GET requests from unrelated accounts.
- Deploy Content Security Policy (CSP) violation reporting to surface inline script execution on wp-admin pages.
Monitoring Recommendations
- Monitor privileged WordPress accounts for anomalous session behavior, including unexpected API calls and plugin configuration changes.
- Alert on modifications to Contact Manager plugin content performed outside standard administrative workflows.
- Track plugin version inventory across WordPress deployments and flag installations still running versions through 8.6.5.
How to Mitigate CVE-2025-8783
Immediate Actions Required
- Update the Contact Manager plugin to the version released in WordPress Changeset #3345750 or later.
- Review all Contact Manager page content for injected scripts and remove any suspicious entries before restoring access.
- Rotate credentials for any administrator accounts that may have interacted with injected pages.
Patch Information
The vendor addressed the vulnerability in the commit tracked by WordPress Changeset #3345750. The fix applies proper sanitization and output escaping to the title parameter. Site operators should upgrade past version 8.6.5 through the WordPress plugin repository.
Workarounds
- Restrict administrator-level access on multi-site WordPress networks to a minimal, trusted set of users.
- Re-enable the unfiltered_html capability for trusted administrators only where organizational policy permits, which excludes those accounts from the affected code path.
- Deactivate the Contact Manager plugin on multi-site installations until the patched version is deployed.
# Update Contact Manager plugin via WP-CLI
wp plugin update contact-manager
wp plugin get contact-manager --field=version
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
