CVE-2026-12939
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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- 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#L337
- 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
- https://www.wordfence.com/threat-intel/vulnerabilities/id/2ca8ab94-45b8-4705-b23b-dbc743572121?source=cve
CWEs
CWE-79
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.