Vulnerability · Published Jul 29, 2026 · Assigned by Wordfence
CVE-2026-12939Newsletters <= 4.15 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'link' Shortcode Attribute
Medium 6.4
In plain English
A medium-severity cross-site scripting in Newsletters from contrid. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 29% of all known vulnerabilities).
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| contrid | Newsletters | 0 – through 4.15 |
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
References
- https://www.wordfence.com/threat-intel/vulnerabilities/id/2ca8ab94-45b8-4705-b23b-dbc743572121?source=cve
- https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.15/helpers/shortcode.php#L337
- https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.15/helpers/shortcode.php#L327
- https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.15/helpers/shortcode.php#L782
- https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.15/includes/checkinit.php#L182
- https://plugins.trac.wordpress.org/changeset?reponame=&old=3621582%40newsletters-lite&new=3621582%40newsletters-lite