Arbitrary File Upload Vulnerability in Auto Thumbnailer Plugin for WordPress
CVE-2025-12154

8.8HIGH

Key Information:

Vendor

WordPress
Status
Auto Thumbnailer
Vendor
CVE Published:
5 December 2025

What is CVE-2025-12154?

The Auto Thumbnailer plugin for WordPress is susceptible to arbitrary file uploads due to inadequate file type validation in the uploadThumb() function. This vulnerability allows authenticated users with Contributor-level access or higher to upload potentially malicious files to the server. If exploited, this flaw may enable remote code execution and compromise the site’s integrity.

Affected Version(s)

Auto Thumbnailer * <= 1.0

References

https://www.wordfence.com/threat-intel/vulnerabilities/id...
https://wordpress.org/plugins/auto-thumbnailer/

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Kenneth Dunn
JSON
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CVE-2025-12154 : Arbitrary File Upload Vulnerability in Auto Thumbnailer Plugin for WordPress