CVE-2026-4278 | Simple Download Counter <= 2.3 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'text' Shortcode Attribute

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.

Published: 2026-03-26 Last update: 2026-04-24 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-4278 is rated Low Risk (31.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-4278

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-26 0.06%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-4278

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
3.1 2.7 [email protected]

Weakness enumeration for CVE-2026-4278

Affected software / configurations for CVE-2026-4278

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-4278

URL Tags
https://plugins.trac.wordpress.org/browser/simple-download-counter/tags/2.3/inc/functions-shortcode.php#L135
https://plugins.trac.wordpress.org/browser/simple-download-counter/tags/2.3/inc/functions-shortcode.php#L157
https://plugins.trac.wordpress.org/browser/simple-download-counter/tags/2.3/inc/functions-shortcode.php#L159
https://plugins.trac.wordpress.org/browser/simple-download-counter/tags/2.3/inc/functions-shortcode.php#L92
https://plugins.trac.wordpress.org/browser/simple-download-counter/trunk/inc/functions-shortcode.php#L135
https://plugins.trac.wordpress.org/browser/simple-download-counter/trunk/inc/functions-shortcode.php#L157
https://plugins.trac.wordpress.org/browser/simple-download-counter/trunk/inc/functions-shortcode.php#L159
https://plugins.trac.wordpress.org/browser/simple-download-counter/trunk/inc/functions-shortcode.php#L92
https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3487364%40simple-download-counter&new=3487364%40simple-download-counter&sfp_email=&sfph_mail=
https://www.wordfence.com/threat-intel/vulnerabilities/id/f23dec73-9031-4829-a84b-4979c8e8ded4?source=cve
cvelogic Threat Intelligence