What’s Vulnerable › Vulnerabilities

CVE-2026-25923: Phar Deserialization leading to Arbitrary File Deletion in my little forum

• Severity: critical (CVSS 9.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-02-09 · updated 2026-06-17
• Weakness: CWE-434

Description

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

• My-Little-Forum mylittleforum: before 20260208.1 — fixed in 20260208.1

How to fix

Upgrade to a fixed version: My-Little-Forum mylittleforum 20260208.1. Check the vendor advisory for mitigations.

References

• https://github.com/My-Little-Forum/mylittleforum/releases/tag/20260208.1
• https://github.com/My-Little-Forum/mylittleforum/security/advisories/GHSA-wr9p-3c3g-78fw

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