WordPress security changelog
MEDIUM CVE-2026-4801 Deferred

Page Builder Gutenberg Blocks – CoBlocks: Cross-site scripting

Page Builder Gutenberg Blocks – CoBlocks is affected by cross-site scripting. Exploitation requires at least contributor-level access. Injected script can execute in the affected site's origin when the vulnerable output is viewed. The published affected range is <= 3.1.16.

CVE / CNA score 6.4 CVSS 3.1 · security@wordfence.com
NVD score Pending NVD has not published its own CVSS assessment.
Component
Page Builder Gutenberg Blocks – CoBlocks
Plugin slug
coblocks
Affected
<= 3.1.16
Safe version
> 3.1.16
Published
Apr 18, 2026
Weakness
CWE-79 — Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

This CVE was published Apr 18, 2026 and is one of 8 known issues for this plugin.

What to do

Update, patch or deactivate.

Update Page Builder Gutenberg Blocks – CoBlocks to a release after 3.1.16, or disable and remove it until a fixed version is available.

A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Source record

Technical description

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.

CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

References

Primary and upstream sources