How to fix CVE-2025-66308?

Within 30 days: Identify affected systems running plugin for Grav is an HTML user interface that provides a co and apply vendor patches as part of regular patch cycle. Verify Content-Security-Policy and output encoding.

Is Grav Plugin Admin affected by CVE-2025-66308?

Organizations using This admin should be aware of moderate risk from CVE-2025-66308, a cross-site scripting vulnerability rated CVSS 5.4. Attackers could inject scripts to steal sessions or perform actions as authenticated users. Proof-of-concept code is publicly available.

CVE-2025-66308

EUVD-2025-200102 MEDIUM

2025-12-01 [email protected]

GHSA-gqxx-248x-g29f

XSS Grav Plugin Admin

5.4

CVSS 3.1

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

Analysis Generated

Mar 15, 2026 - 13:34 vuln.today

EUVD ID Assigned

Mar 15, 2026 - 13:34 euvd

EUVD-2025-200102

Patch Released

Mar 15, 2026 - 13:34 nvd

Patch available

PoC Detected

Dec 03, 2025 - 21:56 vuln.today

Public exploit code

CVE Published

Dec 01, 2025 - 22:15 nvd

MEDIUM 5.4

DescriptionNVD

This admin plugin for Grav is an HTML user interface that provides a convenient way to configure Grav and easily create and modify pages. Prior to 1.11.0-beta.1, a Stored Cross-Site Scripting (XSS) vulnerability was identified in the /admin/config/site endpoint of the Grav application. This vulnerability allows attackers to inject malicious scripts into the data[taxonomies] parameter. The injected payload is stored on the server and automatically executed in the browser of any user who accesses the affected site configuration, resulting in a persistent attack vector. This vulnerability is fixed in 1.11.0-beta.1.

AnalysisAI

Technical ContextAI

Cross-site scripting (XSS) allows injection of client-side scripts into web pages viewed by other users due to insufficient output encoding.

RemediationAI

A vendor patch is available — apply it immediately. Encode all user-supplied output contextually (HTML, JS, URL). Implement Content Security Policy (CSP) headers. Use HTTPOnly and Secure cookie flags.

CVE-2025-66308 vulnerability details – vuln.today

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