Unauthorized Access Vulnerability in Custom Block Builder Plugin for WordPress
CVE-2026-127048

Currently unrated

Key Information:

Vendor

WordPress
Status
Custom Block Builder
Vendor
CVE Published:
15 November 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-127048?

The Custom Block Builder plugin for WordPress prior to version 3.0.0 has a critical flaw in its permission checks for REST routes. It fails to properly deny unauthorized requests, allowing unauthenticated users to manipulate server-side PHP code. This oversight can lead to serious security breaches, enabling attackers to execute arbitrary code remotely on affected installations, jeopardizing the integrity of the site.

Affected Version(s)

Custom Block Builder 0 < 3.0.0

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-127048 - Proof of Concept

References

https://wpscan.com/vulnerability/b88c5a75-56ab-4722-8994-...
exploitvdb-entrytechnical-description

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Mirza Muhammad Sanaullah
WPScan
.