CVE-2026-12939

MediumCVSS 6.4

Published: 29/07/2026(UTC)Updated: 30/07/2026(UTC)Translated: 29/07/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.21%

12th percentile - higher than 12% of all known CVEs

Summary

The Newsletters Lite plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'link' attribute of the post_thumbnail and newsletters_post_thumbnail shortcodes in versions up to and including 4.15 due to insufficient input sanitization and output escaping in the post_thumbnail() method.

Risk Assessment

Authenticated attackers with contributor-level access or higher can inject arbitrary web scripts that execute whenever a user visits an injected page.

Recommendation

Update the plugin to the latest version immediately and use esc_url() and esc_attr() for all shortcode attributes.

Other vulnerabilities in Newsletters Lite

CVE-2026-12938Medium
The Newsletters Lite plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'target' attribute of the [newsletters_post] shortcode in versions up to and including 4.15 due to insufficient input sanitization and output escaping in the posts_single() function and shortcode_posts() handler.

Original NVD description (English source)

The Newsletters Lite plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'link' attribute of the post_thumbnail (and newsletters_post_thumbnail) shortcodes in versions up to and including 4.15. This is due to insufficient input sanitization and output escaping in the post_thumbnail() method in helpers/shortcode.php, which concatenates the user-controlled $link shortcode attribute directly into an href attribute without esc_url() or 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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS