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.
https://github.com/My-Little-Forum/mylittleforum/security/advisories/GHSA-wr9p-3c3g-78fw
https://github.com/My-Little-Forum/mylittleforum/releases/tag/20260208.1
Published: 2026-02-09
Updated: 2026-02-10
Base Score: 5.5
Vector: CVSS2#AV:N/AC:L/Au:S/C:N/I:P/A:P
Severity: Medium
Base Score: 9.1
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Severity: Critical
Base Score: 8.7
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00066