CVE-2026-6378 json
Maxi Blocks <= 2.1.9 - Authenticated (Author+) Stored Cross-Site Scripting via Style Card REST API
published 2026-05-02 6 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-26728
- cvss
- 6.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 14%
- public exploits
- 0
- none known
Summary
The Maxi Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the `/wp-json/maxi-blocks/v1.0/style-card` REST API endpoint in all versions up to, and including, 2.1.9 due to insufficient input sanitization and output escaping of the `sc_styles` parameter. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts that execute on every page where the plugin's style card styles are loaded, including across the entire WordPress admin panel.
Patch / fix
- github.com/maxi-blocks/maxi-blocks#6250 pull request
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6 mo ago
Exploit prediction
0.23% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-08).
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
- ckp267 MaxiBlocks Builder | 17,000+ Design Assets, Patterns, Icons & Starter Sites
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- github.com /maxi-blocks/maxi-blocks/pull/6250/changes/8db3267df9858f684e420566227ed2ea7954d9a9
- wordfence.com /threat-intel/vulnerabilities/id/22f05048-df38-4f26-82a3-53caac995283?source=cve
- plugins.trac.wordpress.org /browser/maxi-blocks/tags/2.1.9/core/class-maxi-api.php#L979
- plugins.trac.wordpress.org /browser/maxi-blocks/tags/2.1.9/core/class-maxi-api.php#L221
- plugins.trac.wordpress.org /browser/maxi-blocks/tags/2.1.9/core/class-maxi-style-cards.php#L197
- plugins.trac.wordpress.org /browser/maxi-blocks/tags/2.1.10/core/class-maxi-api.php#L979
- plugins.trac.wordpress.org /browser/maxi-blocks/tags/2.1.10/core/class-maxi-api.php#L981
- plugins.trac.wordpress.org /browser/maxi-blocks/tags/2.1.10/core/class-maxi-api.php#L987
- plugins.trac.wordpress.org /browser/maxi-blocks/tags/2.1.10/core/class-maxi-api.php#L1010
- plugins.trac.wordpress.org /browser/maxi-blocks/tags/2.1.10/core/class-maxi-api.php#L1021
Sources
- CVE List CVE-2026-6378
- NVD CVE-2026-6378
Fencer Vulns 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.