CVE-2025-23522: HM Portfolio Plugin XSS Vulnerability

CVE-2025-23522 Overview

CVE-2025-23522 is a reflected cross-site scripting (XSS) vulnerability in the Matthew Haines-Young HM Portfolio WordPress plugin (hm-portfolio). The flaw stems from improper neutralization of input during web page generation [CWE-79]. It affects all versions up to and including 1.1.1.

An unauthenticated attacker can craft a malicious URL that, when clicked by a victim, executes attacker-controlled JavaScript in the victim's browser session. Successful exploitation can lead to session hijacking, credential theft, or unauthorized actions performed on behalf of the victim within the WordPress site.

Critical Impact

Attackers can execute arbitrary JavaScript in the context of a victim's browser, enabling theft of session cookies, account takeover, and defacement of the affected WordPress site.

Affected Products

• Matthew Haines-Young HM Portfolio WordPress plugin (hm-portfolio)
• All versions from initial release through 1.1.1
• WordPress sites with the vulnerable plugin installed and active

Discovery Timeline

• 2025-01-24 - CVE-2025-23522 published to NVD
• 2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-23522

Vulnerability Analysis

The vulnerability is a reflected cross-site scripting issue in the HM Portfolio plugin for WordPress. The plugin accepts user-supplied input through HTTP request parameters and reflects that input back into the rendered HTML response without proper sanitization or output encoding.

Because the attack vector is network-based and requires user interaction, an attacker must persuade a victim to click a crafted link. The scope is changed, meaning the injected script can affect resources beyond the vulnerable component, such as authenticated WordPress sessions.

The Exploit Prediction Scoring System (EPSS) currently rates this issue at 0.131% probability with a percentile of 32.055, and no public exploit has been observed.

Root Cause

The root cause is improper neutralization of input during web page generation [CWE-79]. The plugin fails to apply WordPress sanitization functions such as esc_html(), esc_attr(), or wp_kses() on request parameters before echoing them into the HTML response. This allows attacker-controlled markup and script content to be rendered as part of the page.

Attack Vector

An attacker constructs a URL pointing to a vulnerable HM Portfolio endpoint with malicious JavaScript embedded in a reflected parameter. The attacker delivers this URL through phishing, social media, or other social engineering channels.

When a victim, particularly an authenticated administrator, opens the link, the script executes in the browser under the origin of the WordPress site. The payload can read cookies accessible to JavaScript, exfiltrate the WordPress nonce, or issue authenticated requests to the WordPress REST API on behalf of the victim.

Refer to the Patchstack Vulnerability Report for additional technical context.

Detection Methods for CVE-2025-23522

Indicators of Compromise

• HTTP requests to HM Portfolio plugin endpoints containing <script>, javascript:, onerror=, or onload= substrings in query parameters.
• URL-encoded payloads such as %3Cscript%3E or %3Cimg%20src%3Dx%20onerror%3D in WordPress access logs.
• Outbound browser requests from administrator sessions to unfamiliar third-party domains shortly after clicking external links.

Detection Strategies

• Inspect WordPress and reverse-proxy access logs for suspicious query strings targeting wp-content/plugins/hm-portfolio/ paths.
• Deploy a Web Application Firewall (WAF) ruleset that flags reflected XSS patterns in request parameters.
• Correlate referer headers and user-agent strings to identify phishing-driven traffic landing on plugin endpoints.

Monitoring Recommendations

• Enable WordPress audit logging to track administrator account activity, plugin changes, and new user creation.
• Monitor for unexpected modifications to themes, plugins, or wp_options entries that could follow a session hijack.
• Alert on Content Security Policy (CSP) report-uri violations indicating injected inline scripts.

How to Mitigate CVE-2025-23522

Immediate Actions Required

• Identify all WordPress instances with the hm-portfolio plugin installed and confirm the installed version.
• Deactivate and remove the plugin if no patched version is available for your environment.
• Force a password reset and invalidate existing sessions for WordPress administrators who may have clicked suspicious links.

Patch Information

No fixed version is identified in the available advisory data. The vulnerability affects HM Portfolio through 1.1.1. Administrators should consult the Patchstack Vulnerability Report for the latest patch status and remove or replace the plugin until a vendor fix is published.

Workarounds

• Uninstall the HM Portfolio plugin until a verified fix is released by the maintainer.
• Deploy a WAF rule to block requests containing HTML or JavaScript metacharacters in parameters handled by the plugin.
• Implement a strict Content Security Policy that disallows inline scripts and restricts script sources to trusted origins.
• Train administrators to avoid clicking unsolicited links that reference their WordPress domain.

# Example WAF rule (ModSecurity) to block reflected XSS payloads against the plugin path
SecRule REQUEST_URI "@contains /wp-content/plugins/hm-portfolio/" \
    "id:1002301,phase:2,deny,status:403,t:lowercase,t:urlDecodeUni,\
     msg:'CVE-2025-23522 HM Portfolio reflected XSS attempt',\
     chain"
    SecRule ARGS "@rx (?i)(<script|onerror=|onload=|javascript:)" \
        "t:none"