CVE-2026-12939 json
Newsletters <= 4.15 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'link' Shortcode Attribute
published 3mo ago modified 3mo ago also EUVD-2026-50096
- cvss
- 6.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 28%
- public exploits
- 0
- none known
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. 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.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 3mo ago
Exploit prediction
0.35% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N |
Affected products
- contrid Newsletters
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/2ca8ab94-45b8-4705-b23b-dbc743572121?source=cve
- plugins.trac.wordpress.org /browser/newsletters-lite/tags/4.15/helpers/shortcode.php#L337
- plugins.trac.wordpress.org /browser/newsletters-lite/tags/4.15/helpers/shortcode.php#L327
- plugins.trac.wordpress.org /browser/newsletters-lite/tags/4.15/helpers/shortcode.php#L782
- plugins.trac.wordpress.org /browser/newsletters-lite/tags/4.15/includes/checkinit.php#L182
- plugins.trac.wordpress.org /changeset?reponame=&old=3621582%40newsletters-lite&new=3621582%40newsletters-lite
Sources
- CVE List CVE-2026-12939
- NVD CVE-2026-12939
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.