CVE-2024-56026 Overview
CVE-2024-56026 is a reflected Cross-Site Scripting (XSS) vulnerability in the SiteOrigin Simple Proxy WordPress plugin developed by Greg. The flaw stems from improper neutralization of user-supplied input during web page generation [CWE-79]. Attackers can craft malicious URLs that, when clicked by an authenticated user, execute arbitrary JavaScript in the victim's browser session. The vulnerability affects all versions of Simple Proxy up to and including 1.0. Exploitation requires user interaction but does not require attacker authentication, and the scope is changed because injected scripts execute in the context of the WordPress site.
Critical Impact
Successful exploitation allows attackers to execute arbitrary JavaScript in a victim's browser, potentially leading to session hijacking, credential theft, or unauthorized actions performed in the user's WordPress context.
Affected Products
- SiteOrigin Simple Proxy plugin for WordPress (simple-proxy)
- All versions from n/a through 1.0
- WordPress sites with the plugin installed and active
Discovery Timeline
- 2025-01-02 - CVE CVE-2024-56026 published to NVD
- 2026-04-28 - Last updated in NVD database
Technical Details for CVE-2024-56026
Vulnerability Analysis
The Simple Proxy plugin processes HTTP request parameters and reflects them into the rendered HTML response without proper output encoding or sanitization. When a victim visits a crafted URL containing JavaScript payloads in vulnerable parameters, the browser interprets the reflected content as executable script. Because the scope is marked as changed in the CVSS vector, the injected payload can affect resources beyond the vulnerable component itself, including session cookies and authenticated WordPress sessions. Reflected XSS in administrative-facing plugin endpoints poses elevated risk because a targeted administrator click can lead to plugin or theme modification, content tampering, or pivoting to broader site compromise. The vulnerability is classified under [CWE-79] (Improper Neutralization of Input During Web Page Generation).
Root Cause
The plugin fails to apply escaping functions such as esc_html(), esc_attr(), or wp_kses() to user-controlled input before embedding it into the HTML response. Without contextual output encoding, attacker-supplied markup is rendered as live HTML and JavaScript rather than inert text.
Attack Vector
An attacker constructs a malicious URL that includes a JavaScript payload in a query parameter handled by the Simple Proxy plugin. The attacker then delivers this URL through phishing emails, social media posts, or compromised third-party sites. When a logged-in WordPress user, particularly an administrator, opens the link, the browser renders the reflected payload and executes the attacker's script with the user's privileges on the target site.
No verified public proof-of-concept code is available. Refer to the Patchstack WordPress Vulnerability Report for additional technical context.
Detection Methods for CVE-2024-56026
Indicators of Compromise
- Web server access logs containing requests to Simple Proxy endpoints with suspicious query parameters such as <script>, onerror=, javascript:, or URL-encoded equivalents (%3Cscript%3E).
- Unexpected outbound HTTP requests from administrator browsers to attacker-controlled domains shortly after clicking external links.
- WordPress audit log entries showing administrative actions that originated from unusual referrers or short sessions.
Detection Strategies
- Inspect HTTP request parameters destined for the simple-proxy plugin for HTML special characters and known XSS payload patterns.
- Deploy a Web Application Firewall (WAF) rule set that flags reflected parameters echoed verbatim in HTML responses.
- Correlate authenticated WordPress admin sessions with anomalous referrer headers pointing to external phishing infrastructure.
Monitoring Recommendations
- Enable WordPress audit logging to track configuration changes, new user creation, and plugin or theme edits.
- Forward web server access logs to a centralized log analytics platform and alert on XSS signature matches.
- Monitor browser Content Security Policy (CSP) violation reports for inline script execution attempts on plugin pages.
How to Mitigate CVE-2024-56026
Immediate Actions Required
- Deactivate and remove the Simple Proxy plugin until a vendor-supplied fix is verified for the installed version.
- Audit WordPress administrator and editor accounts for unauthorized changes made since the plugin was first installed.
- Force a password reset and session invalidation for all privileged WordPress users.
Patch Information
At the time of NVD publication, no fixed version has been listed for the Simple Proxy plugin. The vulnerability affects all releases through 1.0. Consult the Patchstack WordPress Vulnerability Report for ongoing remediation updates and replace the plugin with a maintained alternative if no patch becomes available.
Workarounds
- Remove the simple-proxy plugin directory from wp-content/plugins/ if it is not business-critical.
- Deploy a WAF rule that strips or blocks HTML metacharacters in query parameters routed to plugin endpoints.
- Enforce a strict Content Security Policy that disallows inline scripts and restricts script sources to trusted origins.
- Train administrators to avoid clicking unverified links while logged in to the WordPress admin console.
# Example WAF rule (ModSecurity) blocking reflected XSS payloads on plugin endpoints
SecRule REQUEST_URI "@contains /wp-content/plugins/simple-proxy/" \
"phase:2,deny,status:403,id:1056026,\
chain,msg:'Block reflected XSS attempt against Simple Proxy plugin'"
SecRule ARGS "@rx (?i)(<script|onerror=|javascript:|%3Cscript)" "t:none,t:urlDecodeUni"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
