CVE-2026-4278
Stored XSS in Simple Download Counter WordPress Plugin Allows Script Injection
Publication date: 2026-03-26
Last updated on: 2026-03-26
Assigner: Wordfence
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| wordfence | simple_download_counter | to 2.3 (inc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-79 | The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. |
Attack-Flow Graph
AI Powered Q&A
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability involves Stored Cross-Site Scripting (XSS) in the Simple Download Counter WordPress plugin via the 'sdc_menu' shortcode, specifically through the 'text' and 'cat' shortcode attributes. Detection involves identifying if your WordPress site is running the vulnerable plugin version (up to and including 2.3) and if the shortcode is used with unescaped user input.
To detect this vulnerability on your system, you can check the installed plugin version and scan for usage of the 'sdc_menu' shortcode with potentially malicious input.
- Check the installed version of the Simple Download Counter plugin via WordPress admin dashboard or by inspecting the plugin files (look for version 2.3 or earlier).
- Search your WordPress content (posts, pages) for usage of the '[sdc_menu]' shortcode with 'text' or 'cat' attributes that might contain suspicious or script-like content.
- Use WP-CLI commands to find shortcode usage, for example: wp post list --post_type=page,post --field=ID | xargs -I % wp post get % --field=post_content | grep -i '\[sdc_menu'
- Monitor HTTP requests and responses for injected scripts in pages that use the shortcode, especially from users with Contributor-level access or higher.
What immediate steps should I take to mitigate this vulnerability?
The primary mitigation step is to update the Simple Download Counter plugin to version 2.3.1 or later, where the vulnerability has been fixed by properly sanitizing and escaping shortcode attributes.
- Update the plugin to version 2.3.1 or newer as released on March 20, 2026, which includes fixes applying esc_attr() and esc_html() to user-supplied shortcode attributes.
- Restrict Contributor-level and higher user permissions to trusted users only, as the vulnerability requires authenticated users with at least Contributor access to exploit.
- Audit existing content for injected scripts or malicious shortcode usage and remove or sanitize any suspicious entries.
- Implement Web Application Firewall (WAF) rules to detect and block attempts to inject scripts via shortcode attributes.
Can you explain this vulnerability to me?
The Simple Download Counter plugin for WordPress is vulnerable to Stored Cross-Site Scripting (XSS) via the 'sdc_menu' shortcode in all versions up to and including 2.3. This vulnerability arises because the plugin does not properly sanitize or escape user-supplied shortcode attributes, specifically the 'text' and 'cat' attributes.
The 'text' attribute is output directly into HTML content without escaping, and the 'cat' attribute is used unescaped in HTML class attributes. This allows authenticated attackers with Contributor-level access or higher to inject arbitrary malicious scripts into pages. These scripts execute whenever any user accesses the infected page, potentially compromising user data or site integrity.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The vulnerability in the Simple Download Counter plugin is a Stored Cross-Site Scripting (XSS) issue that allows authenticated users with Contributor-level access or higher to inject arbitrary scripts into pages. This can lead to unauthorized script execution when other users access the affected pages.
Such XSS vulnerabilities can impact compliance with common standards and regulations like GDPR and HIPAA because they may lead to unauthorized access or exposure of personal data, session hijacking, or other malicious activities that compromise data confidentiality and integrity.
Specifically, GDPR requires organizations to implement appropriate technical and organizational measures to protect personal data against unauthorized or unlawful processing and against accidental loss, destruction, or damage. An XSS vulnerability that allows script injection undermines these protections.
Similarly, HIPAA mandates safeguards to ensure the confidentiality, integrity, and availability of electronic protected health information (ePHI). Exploitation of this XSS vulnerability could potentially lead to breaches of ePHI confidentiality.
Therefore, the presence of this vulnerability could result in non-compliance with these regulations if exploited, especially if personal or sensitive data is involved or if the vulnerability is not remediated in a timely manner.
How can this vulnerability impact me? :
This vulnerability can allow an attacker with Contributor-level access or above to inject malicious JavaScript code into pages via shortcode attributes. When other users visit these pages, the injected scripts execute in their browsers.
- Execution of arbitrary scripts can lead to theft of user credentials or session tokens.
- It can enable unauthorized actions on behalf of users (e.g., performing actions with their privileges).
- It may allow defacement of the website or redirection to malicious sites.
- Overall, it compromises the confidentiality and integrity of the website and its users.