Custom Block Builder – Lazy Blocks <= 4.2.0 - Authenticated (Contributor+) Remote Code Execution

2026-02-10 00:00

Youssef Elouaer

Strategic Overview

Status

Patched in 4.2.1

Affected PluginCustom Block Builder – Lazy Blocks

Affected Version<= 4.2.0

CVSS8.8High

CVECVE-2026-1560

View all Custom Block Builder – Lazy Blocks vulnerabilities

Vulnerability Overview

The Custom Block Builder – Lazy Blocks plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 4.2.0 via multiple functions in the 'LazyBlocks_Blocks' class. This makes it possible for authenticated attackers, with Contributor-level access and above, to execute code on the server.

Technical Analysis

REMEDIATION: Update to version 4.2.1, or a newer patched version --- IDENTIFIER: CWE-94 (Improper Control of Generation of Code ('Code Injection')) The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

External References

https://www.cve.org/CVERecord?id=CVE-2026-1560 https://www.wordfence.com/threat-intel/vulnerabilities/id/b1853c88-277b-4955-b042-aeed1cffb49b

CVSS Vector

8.8

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

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