Flex Guten <= 1.2.5 - Authenticated (Contributor+) Stored Cross-Site Scripting via thumbnailHoverEffect Parameter

2025-08-05 13:00

Peter Thaleikis

Strategic Overview

Status

Patched in 1.2.6

Affected PluginFlex Guten – Multile Blocks

Affected Version<= 1.2.5

CVSS6.4Medium

CVECVE-2025-6256

View all Flex Guten – Multile Blocks vulnerabilities

Vulnerability Overview

The Flex Guten plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘thumbnailHoverEffect’ parameter in all versions up to, and including, 1.2.5 due to insufficient input sanitization and output escaping. 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.

Technical Analysis

REMEDIATION: Update to version 1.2.6, or a newer patched version --- IDENTIFIER: CWE-79 (Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

External References

https://www.cve.org/CVERecord?id=CVE-2025-6256 https://www.wordfence.com/threat-intel/vulnerabilities/id/ca149cc0-b256-41cd-b64d-dd905bd72602

CVSS Vector

6.4

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

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