CVE-2026-18488 json
Blocksy Companion <= 2.1.51 - Authenticated (Author+) Stored Cross-Site Scripting via 'tagName' Block Attribute (blocksy/dynamic-data)
published 2026-09-01 2 mo ago modified 2026-09-01 2 mo ago also EUVD-2026-68987
- cvss
- 6.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 36%
- public exploits
- 0
- none known
Summary
The Blocksy Companion plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'tagName' Block Attribute (blocksy/dynamic-data) in all versions up to, and including, 2.1.51 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with author-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.42% chance of exploitation in the next 30 days, higher than 36% 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
- creativethemeshq Blocksy Companion
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/e0d0adcc-6741-4cab-aaba-df356691a1ee?source=cve
- plugins.trac.wordpress.org /browser/blocksy-companion/tags/2.1.51/framework/features/blocks/dynamic-data/views/wp-field.php#L487
- plugins.trac.wordpress.org /browser/blocksy-companion/tags/2.1.51/framework/features/blocks/dynamic-data/views/wp-field.php#L448
- plugins.trac.wordpress.org /browser/blocksy-companion/tags/2.1.51/framework/features/blocks/dynamic-data/block.php#L183
- plugins.trac.wordpress.org /browser/blocksy-companion/tags/2.1.51/static/js/editor/blocks/dynamic-data/block.json#L7
- plugins.trac.wordpress.org /browser/blocksy-companion/tags/2.1.4/framework/features/blocks/dynamic-data/views/wp-field.php#L487
- plugins.trac.wordpress.org /browser/blocksy-companion/tags/2.1.4/framework/features/blocks/dynamic-data/views/wp-field.php#L448
- plugins.trac.wordpress.org /browser/blocksy-companion/tags/2.1.4/framework/features/blocks/dynamic-data/block.php#L183
- plugins.trac.wordpress.org /browser/blocksy-companion/tags/2.1.4/static/js/editor/blocks/dynamic-data/block.json#L7
- plugins.trac.wordpress.org /changeset/3636709/blocksy-companion/trunk/framework/features/blocks/dynamic-data/views/wp-field.php
- plugins.trac.wordpress.org /changeset?old_path=%2Fblocksy-companion/tags/2.1.51&new_path=%2Fblocksy-companion/tags/2.1.52
Sources
- CVE List CVE-2026-18488
- NVD CVE-2026-18488
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.