CVE-2026-4278
CWE-79Published: March 26, 2026· Updated: Mar 30, 2026
Official Description
The Simple Download Counter plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'sdc_menu' shortcode in all versions up to, and including, 2.3. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes, specifically the 'text' and 'cat' attributes. The 'text' attribute is output directly into HTML content on line 159 without any escaping (e.g., esc_html()). The 'cat' attribute is used unescaped in HTML class attributes on lines 135 and 157 without esc_attr(). This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Technical Analysis
CVE-2026-4278 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
All References (10)
Quick Facts
Related CVEs (CWE-79)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-4278 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts