CVE-2026-9601 json
Stackable <= 3.19.9 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'save' Parameter
published 2026-11-07 2 d ago modified 2026-11-07 38 h ago also EUVD-2026-118904
- 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 23%
- public exploits
- 0
- none known
Summary
The Stackable – Page Builder Gutenberg Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'update_block_style' endpoint in all versions up to, and including, 3.19.9 due to insufficient input sanitization and output escaping. 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.
Patch / fix
- github.com/gambitph/Stackable#3725 pull request
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 38 h ago
Exploit prediction
0.31% chance of exploitation in the next 30 days, higher than 23% 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 |
| NVD | 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
- bfintal Stackable – Page Builder Gutenberg Blocks
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- github.com /gambitph/Stackable/pull/3725
- wordfence.com /threat-intel/vulnerabilities/id/1d4da874-23c8-4df4-b776-6046ce8d705a?source=cve
- plugins.trac.wordpress.org /browser/stackable-ultimate-gutenberg-blocks/tags/3.19.6/src/deprecated/block-defaults/custom-block-styles.php
- plugins.trac.wordpress.org /browser/stackable-ultimate-gutenberg-blocks/tags/3.19.8/src/deprecated/block-defaults/custom-block-styles.php
- plugins.trac.wordpress.org /browser/stackable-ultimate-gutenberg-blocks/tags/3.19.8/src/deprecated/block-defaults/custom-block-styles.php
- plugins.trac.wordpress.org /browser/stackable-ultimate-gutenberg-blocks/tags/3.19.8/src/deprecated/block-defaults/custom-block-styles.php
- plugins.trac.wordpress.org /browser/stackable-ultimate-gutenberg-blocks/tags/3.19.8/src/deprecated/block-defaults/custom-block-styles.php
- plugins.trac.wordpress.org /browser/stackable-ultimate-gutenberg-blocks/tags/3.19.6/src/deprecated/block-defaults/custom-block-styles.php
- plugins.trac.wordpress.org /browser/stackable-ultimate-gutenberg-blocks/tags/3.19.6/src/deprecated/block-defaults/custom-block-styles.php
- plugins.trac.wordpress.org /browser/stackable-ultimate-gutenberg-blocks/tags/3.19.6/src/deprecated/block-defaults/custom-block-styles.php
- plugins.trac.wordpress.org /changeset/3609541/stackable-ultimate-gutenberg-blocks/trunk/src/deprecated/block-defaults/custom-block-styles
Sources
- CVE List CVE-2026-9601
- NVD CVE-2026-9601
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.