CVE-2026-4801CWE-79

Page Builder Gutenberg Blocks <= 3.1.16 - Authenticated (Contributor+) Stored Cross-Site Scripting via External iCal Feed Data

Medium · published April 18, 2026

CVSS v3.1
6.4
EPSS
0%
Percentile
36.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.4 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00435 · 36.7th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-04-18T03:37Z
EPSS history
Timeline
  • 18 APR 03:37Z
    Page Builder Gutenberg Blocks <= 3.1.16 - Authenticated (Contributor+) Stored Cross-Site Scripting via External iCal Feed Data
    cvelistv5