CVE-2026-12939

MEDIUM 6.4

Newsletters <= 4.15 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'link' Shortcode Attribute

CVSS Score

6.4

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-79
Vendor	contrid
Product	newsletters
Published	Jul 29, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Scope

Confidentiality

Integrity

Availability

Affected Versions

contrid / Newsletters

0 ≤ 4.15

References

NVD ↗ CVE.org ↗ EPSS Data ↗

Credits

Wordfence PRISM