CVE-2026-8899

The Auto Thumbnail plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'thumbnails' shortcode in all versions up to, and including, 1.0. This is due to insufficient input sanitization and output escaping on the shortcode's 'width' and 'height' attributes in the athn_thumbnails() function, which are concatenated directly into an HTML <img> tag. 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.

CVSS v3 6.4 MEDIUM

6.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.1 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://plugins.trac.wordpress.org/browser/automatic-thumbnail/tags/1.0/index.php#L13
https://plugins.trac.wordpress.org/browser/automatic-thumbnail/tags/1.0/index.php#L34
https://www.wordfence.com/threat-intel/vulnerabilities/id/f0cc349a-96f9-4b11-a0b4-28bc4ccc022c?source=cve

Configurations

No configuration.

History

27 May 2026, 07:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-27 07:16

Updated : 2026-06-17 11:04

NVD link : CVE-2026-8899

Mitre link : CVE-2026-8899

CVE.ORG link : CVE-2026-8899

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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