CVE-2026-4801 json
Page Builder Gutenberg Blocks <= 3.1.16 - Authenticated (Contributor+) Stored Cross-Site Scripting via External iCal Feed Data
published 2026-04-18 6 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-23650
- 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 35%
- public exploits
- 0
- none known
Summary
The Page Builder Gutenberg Blocks – CoBlocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via external iCal feed data in all versions up to, and including, 3.1.16 due to insufficient output escaping of event titles, descriptions, and locations fetched from external iCal feeds in the Events block rendering function. 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.
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6 mo ago
Exploit prediction
0.41% chance of exploitation in the next 30 days, higher than 35% 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
- godaddy Page Builder Gutenberg Blocks – CoBlocks
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/bde0aef3-aa61-4ee7-9cbf-9f51cb5ac700?source=cve
- plugins.trac.wordpress.org /browser/coblocks/trunk/src/blocks/events/index.php#L218
- plugins.trac.wordpress.org /browser/coblocks/tags/3.1.16/src/blocks/events/index.php#L218
- plugins.trac.wordpress.org /browser/coblocks/trunk/src/blocks/events/index.php#L245
- plugins.trac.wordpress.org /browser/coblocks/tags/3.1.16/src/blocks/events/index.php#L245
- plugins.trac.wordpress.org /browser/coblocks/trunk/src/blocks/events/index.php#L246
- plugins.trac.wordpress.org /browser/coblocks/tags/3.1.16/src/blocks/events/index.php#L246
- plugins.trac.wordpress.org /browser/coblocks/trunk/src/blocks/events/index.php#L255
- plugins.trac.wordpress.org /browser/coblocks/tags/3.1.16/src/blocks/events/index.php#L255
- plugins.trac.wordpress.org /browser/coblocks/trunk/src/blocks/events/index.php#L91
- plugins.trac.wordpress.org /browser/coblocks/tags/3.1.16/src/blocks/events/index.php#L91
- plugins.trac.wordpress.org /changeset/3475789/coblocks/trunk/src/blocks/events/index.php
- plugins.trac.wordpress.org /changeset?old_path=%2Fcoblocks/tags/3.1.16&new_path=%2Fcoblocks/tags/3.1.17
Sources
- CVE List CVE-2026-4801
- NVD CVE-2026-4801
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.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.