CVE-2026-25923: Mylittleforum My Little Forum

Critical severity, CVSS 9.1. EPSS: 0.7% chance of exploitation in the next 30 days.

my little forum is a PHP and MySQL based internet forum that displays the messages in classical threaded view. Prior to 20260208.1, the application fails to filter the phar:// protocol in URL validation, allowing attackers to upload a malicious Phar Polyglot file (disguised as JPEG) via the image upload feature, trigger Phar deserialization through BBCode [img] tag processing, and exploit Smarty 4.1.0 POP chain to achieve arbitrary file deletion. This vulnerability is fixed in 20260208.1.

Affected products

• Mylittleforum My Little Forum: before 20260208.1 (fixed in 20260208.1)

Published 2026-02-09. Last modified 2026-06-17.