CVE-2026-0894CWE-79

Content Blocks (Custom Post Widget) <= 3.3.9 - Authenticated (Author+) Stored Cross-Site Scripting via content_block Shortcode

Medium · published April 18, 2026

CVSS v3.1
6.4
EPSS
0%
Percentile
8.6
In the wild
Unconfirmed
What it is

The Content Blocks (Custom Post Widget) plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's content_block shortcode in all versions up to, and including, 3.3.9 due to insufficient input sanitization and output escaping on user supplied values consumed from user-created content blocks. 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
0.00194 · 8.6th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-04-18T09:26Z
EPSS history
Timeline
  • 18 APR 09:26Z
    Content Blocks (Custom Post Widget) <= 3.3.9 - Authenticated (Author+) Stored Cross-Site Scripting via content_block Shortcode
    cvelistv5